Sermorelin: The Definitive Guide

What is sermorelin?

Sermorelin is a lab-made peptide that copies the first 29 amino acids of growth-hormone-releasing hormone, the signal the brain uses to tell the pituitary gland to release growth hormone. It makes the body release its own growth hormone rather than supplying it. It was once an FDA-approved medicine called Geref, but no approved product is sold today. [1], [2], [3]

Growth-hormone-releasing hormone (GHRH) comes from the hypothalamus at the base of the brain and travels a very short distance to the pituitary gland. The natural hormone has 44 amino acids, but the first 29 are enough to switch on the pituitary's growth-hormone-making cells, which is why the fragment works. Sermorelin's chain matches the human sequence exactly, with a small chemical cap on its end. Because it makes the body release its own growth hormone, it is called a growth hormone secretagogue. [2], [4], [1]

Why was the approved version discontinued?

Geref was approved in the United States twice: in 1990 as a one-time intravenous test of whether the pituitary can release growth hormone, and in 1997 as a nightly injection for children with growth-hormone deficiency who were growing too slowly. The maker discontinued both in 2008, and FDA withdrew the approvals in 2009. [5], [6], [3]

In 2013, FDA formally determined that Geref was not withdrawn for reasons of safety or effectiveness. An FDA review later described the withdrawal as a business decision, because the active ingredient was no longer being manufactured. [3], [7]

That history explains the mix of sources you will find. The old label gives weight-based doses for children and a test dose, while today's sermorelin is compounded by pharmacies on prescription or sold as "research" vials, and adult protocols come from clinics and websites rather than from the label. FDA does not review compounded drugs for safety, effectiveness or quality before they are sold. [2], [8], [9], [10]

Typical Sermorelin Protocols

Most reviewed sources give sermorelin as one subcutaneous injection at bedtime, somewhere in the range of 200–500 mcg, and the source of the table above puts most people at 200–300 mcg, 5 nights a week, for about 3–6 months. Across 27 current protocol pages that state an amount or range, the median low end was 200 mcg and the median high end 500 mcg. Of the 25 pages that say how often to take it, 13 give it every night, 6 give it on 5 nights and 6 allow either. [11], [10], [12], [13], [14], [15], [16]

Titration Changing the amount in steps

The usual approach starts at 100–200 mcg for the first 1–2 weeks and moves to 200–300 mcg once sleep and the injection site are settled. Some pages continue upward by about 100 mcg every 1–2 weeks to 300–500 mcg, and several clinics adjust the dose by an IGF-1 blood test at 6–8 weeks, up to 500–600 mcg. [11], [17], [18], [19], [20] In community education groups, members most often start at 200 mcg and some work up to 500 mcg over about 12 weeks; several cut back after side effects.

Breaks and cycles

About a quarter of the pages that give a frequency skip two nights a week (5 nights on, 2 off); the rest give it every night or allow either. Courses of 3–6 months are the most often described, sometimes followed by 1–3 months off. The stated reason is to keep the pituitary responsive, but no study has tested whether breaks are needed or helpful. [11], [21], [10], [22] Educators in community education groups give anything from 8 to 16 weeks on with 4–8 weeks off to continuous use, and some members report using it nightly for one to two years.

Read the units: these amounts are in micrograms. 1 mg equals 1,000 mcg, so 0.3 mg is 300 mcg. The amount each time and the weekly total are separate columns: 300 mcg on 5 nights is a 1,500 mcg weekly total. Compounded liquids come in different strengths, so the same number of syringe units can hold very different amounts; see how micrograms convert to syringe units.

Each row is a complete schedule as its source published it, and the rows are alternatives, not steps to move through. These schedules come from clinic and protocol websites, not clinical trials: the approved label dosed children by body weight, and the adult studies used larger amounts (see the next table). [11], [2], [10]

Cautions for every schedule above: allergic reactions can appear after weeks or months of trouble-free use and come back on restarting (see allergic reactions). The old label warned that the recommended dose "should not be exceeded", required thyroid tests before and during treatment, and was not tested in people whose growth-hormone problem came from a brain tumor or other lesion. Sermorelin is banned in sport at all times, and it has not been studied in pregnancy or in people with cancer. [2], [23]

What doses did the approved label and the studies use?

The largest adult study doses were several times the typical website amount: about 1 mg every evening for months, and up to 2 mg a day for shorter periods. No study has tested the flat 200–500 mcg bedtime dose that most clinics and websites use, and the one page that claims an "FDA-era label" set adult doses of 0.2–0.3 mg a day is wrong: the only approved adult use was the one-time intravenous test. [27], [25], [26], [12], [29]

What are the usual sermorelin and ipamorelin blend amounts?

Many clinics and users pair sermorelin with ipamorelin, a peptide that releases growth hormone through a different receptor, either drawn into one syringe or sold premixed. One protocol source gives these combinations, with the amounts per peptide; compounding pharmacies have sold premixed vials such as 15 mg of ipamorelin with 9 or 18 mg of sermorelin. [30], [31]

No study has tested sermorelin with ipamorelin. In community education groups, typical pairings are 200–300 mcg of sermorelin with 100–200 mcg of ipamorelin at bedtime, often 5 nights a week. In a premixed blend, the dose on the syringe is the blend total: one forum member worked out that a "500 mcg" dose of a three-peptide blend held only 200 mcg of sermorelin. [32]

What is sermorelin commonly used for?

Most adults who look into sermorelin want better sleep, easier recovery from training, less body fat, more lean muscle or a general "anti-aging" effect, and they usually get it through telehealth clinics, compounding pharmacies or research vendors. Many are also taking testosterone, hormone therapy for menopause or a GLP-1 weight-loss medicine such as tirzepatide or semaglutide. [40], [41], [33]

The evidence behind those goals is thin. Sermorelin's approved uses were a pituitary test and growth treatment in children. In adults, what exists is a handful of small studies in older people that measured hormones, body composition and a few functional outcomes, plus personal accounts. A 2026 review concluded that its benefits in healthy people are uncertain because the human evidence is "limited and largely indirect". [2], [40]

Sleep

Better sleep is the benefit people report most, often within the first week or two. It is also where the studies disagree with the stories. In the one placebo-controlled trial of sermorelin that had sleep as an aim, about 1 mg every evening for months did not improve sleep quality in healthy older adults; the sermorelin group's sleep questionnaire scores got slightly worse. [27], [28], [42]

Laboratory studies that gave GHRH as quick injections into a vein at night did deepen sleep in young men under some conditions, but the effect was much weaker in older people, absent with a steady infusion and reversed in young women. Those studies do not say which form of GHRH they used, and none tested a bedtime injection of sermorelin. See what the sleep studies found and what people report.

Body fat, muscle and strength

In the placebo-controlled trials in older adults, sermorelin shifted body composition a little: body fat fell about 5% with a matching gain in lean mass, less so in women taking oral estrogen. Strength and aerobic fitness did not improve. A shorter study of 2 mg nightly for 6 weeks in older men found no change in body composition at all. [27], [28], [26]

No study has tested sermorelin for building muscle or losing fat in younger adults. People who report visible changes are nearly always also dieting, training, or taking testosterone or a GLP-1 medicine.

Recovery, joints and injuries

No study has measured recovery, joint pain or injury healing with sermorelin, in people or in animals. Some users on testosterone therapy credit it with easier recovery or less joint pain, while others notice nothing, and one clinic operator said it helped general recovery but not a rotator-cuff injury. [43], [44], [45]

Memory and thinking

The same placebo-controlled program reported small improvements on several thinking tests after 6 months in 89 healthy older adults. That is one study, reported alongside tests that did not change, and it has not been repeated with sermorelin. [46], [27]

Testing and treating growth-hormone problems

Doctors once used Geref to test the pituitary and to treat children with growth-hormone deficiency whose pituitary could still respond to it. Both uses ended with the product in 2008, and in the trials that compared them in children, growth hormone did better than sermorelin at its usual dose. See the children's studies. [47], [48], [49]

Other uses you may come across

Websites also claim benefits for skin, hair, bone density, immunity, libido and mood. None of these has been tested for sermorelin in people. One 2021 computer analysis of drugs for brain tumors named sermorelin, but it contains no treatment data and is not evidence of any effect against cancer. [50]

Where do sermorelin protocols differ?

Sources disagree about more than the amount: where a dose comes from, whether it is scaled to body weight, how often and when it is taken, how long a course runs, and what to combine it with.

Is the dose from the old label, a study or a clinic?

Check the source before copying a number. The label gives 30 mcg per kilogram for children and 1 mcg per kilogram for an intravenous test; the adult studies used 0.5–2 mg; and clinics and websites use a flat 100–500 mcg. These come from different people, goals and routes, and none of the adult website schedules was tested. [2], [24], [25], [26], [10]

Several pages get the research wrong. The most common error is to describe "the adult sermorelin trial" as a 1997 study of 19 older adults: that study used a modified version of GHRH with one amino acid swapped, not sermorelin. Another page says the 1997 study of 2 mg nightly raised IGF-1, when it did not, and one cites a "2018 trial of 500 mcg nightly" that we could not find in any database. [51], [52], [53], [54], [26]

Doserly

Tested doses compared with website doses

Bars share one scale from 0 to 2,200 mcg a day.

Most common website schedule: 200–300 mcg

Nightly or 5 nights a week; never tested in a study.

Full range on 27 protocol pages: 100–600 mcg

medians: 200 mcg low end, 500 mcg high end.

Older men and women, 5–6 months: about 1,000 mcg

placebo-controlled; about 14 mcg/kg each evening.

Older men, 1992, 14 days: 1,000–2,000 mcg

0.5 mg or 1 mg twice a day.

Older men, 1997, 6 weeks: 2,000 mcg

2 mg once nightly; IGF-1 did not change.

Children's label, 30 kg child: 900 mcg

30 mcg/kg nightly; children only.

Diagnostic test, 70 kg adult: 70 mcg once

1 mcg/kg once, into a vein; a test, not a treatment.

Amounts per day. Weight-based rows show a 30 kg child or a 70 kg adult as examples.

The flat 200–300 mcg bedtime dose used online sits well below what the adult studies gave and was never itself tested.

Flat dose or per kilogram?

The label and the University of Washington trials dosed by body weight, so a heavier person got more. Some websites try to bring this back with 1–5 mcg per kilogram a day, but that range comes from the one-time intravenous test dose, not from any treatment schedule. A subcutaneous injection delivers only about 6% as much drug to the blood as the same amount given into a vein, so the two cannot be swapped. [2], [27], [36], [37]

Every night, or 5 nights a week?

Both are common. The label gave it every night, and so do just over half of the websites that state a frequency; many clinics and protocol pages instead skip two nights a week, a pattern written as 5 on, 2 off, to "prevent desensitization". No study has compared the two, and the evidence on whether the pituitary gets used to sermorelin is mixed (see "Does the body get used to it?"). [2], [16], [11], [17]

Bedtime, morning or twice a day?

Most sources give one dose at bedtime, to line up with the body's largest growth-hormone release early in the night. The label also said bedtime, but no study has compared dosing times in adults, and in the placebo-controlled trial the evening dose produced one large growth-hormone burst without restoring the normal night-time pattern. [2], [27]

Some clinics prescribe it two or three times a day, and a compounding pharmacist told one user that some people feel wired rather than sleepy and take it in the morning. Users whose sleep got worse often moved it to the morning. [55], [56], [57], [58], [59]

Does it have to be taken on an empty stomach?

Most sources say to inject at least 1–2 hours after eating, and members of community education groups taking GLP-1 medicines, which slow digestion, often wait 3 hours or more. There is a reason behind the advice: in a lab test, a glucose drink lowered the growth-hormone peak after GHRH from 11.6 to 7.4 mcg/L. But a different study found that GHRH given 3.5 hours after glucose produced a larger peak, and no study has tested sermorelin injections with and without food. [11], [37], [60], [61]

Start low, or start high?

Most current sources start at 100–200 mcg and move up. Others do not: some telehealth clinics have prescribed 600–1,000 mcg from the first night, and a 2013–2017 telehealth practice started at 1,000 mcg nightly and reduced it over time. [11], [17], [62], [63], [39]

Personal accounts suggest that a lower start is easier to tolerate. One user prescribed 600 mcg found it too strong and cut back to 200 mcg; others describe sleeping worse, or waking after 4–5 hours, above about 200–300 mcg, and sleeping well again after lowering the dose. [64], [65], [66], [67]

How long is a course, and are breaks needed?

Sources most often describe 3–6 months on, some followed by 1–3 months off; some members of community education groups use it nightly for years. The case for breaks rests on short-term data. In children given a continuous subcutaneous infusion from a small pump, the growth-hormone response rose at first and then declined over 3–6 months, and in cells the receptor stops responding within hours of constant exposure. Nobody has tested nightly injections with and without breaks. [11], [21], [68], [69]

Is more always better?

No, and "you cannot overdose" is a myth. Some pages claim the brain's own brake on growth hormone makes an overdose "difficult if not impossible"; that comes from a two-page opinion article, not data. In children, higher continuous doses raised baseline growth hormone, and twice-daily injections raised fasting blood sugar and insulin. The label itself says the recommended dose "should not be exceeded". [70], [71], [72], [2]

At the other end, some pages say doses above 500 mcg add nothing. In the 1992 study, only the higher dose (1 mg twice daily) brought growth hormone and IGF-1 up to young-adult levels in older men, so the ceiling claim is not established either. [11], [37], [25]

Can it be combined with ipamorelin, GHRP-2 or GHRP-6?

People often do, on the reasoning that ipamorelin and the GHRPs act on a different receptor. In single intravenous tests, GHRH plus GHRP-6 released more growth hormone in healthy adults than the two added together, while the 29-amino-acid GHRH plus GHRP-2 simply added up. Neither study used ipamorelin or repeated injections, and no human study has tested sermorelin with ipamorelin. [73], [74], [31]

Combinations also make side effects harder to trace. Users describe flushing and sweating, pounding heartbeat on waking and hunger more often with blends than with sermorelin alone. [75], [76], [77] Read the Doserly guides to ipamorelin, GHRP-2 and GHRP-6.

Can it be combined with CJC-1295 or tesamorelin?

Educators in community education groups consistently advise against it, because CJC-1295 and tesamorelin act on the same GHRH receptor, so a second one adds exposure without a new mechanism. A few members do it anyway. No study has tested either combination. Read the Doserly guides to CJC-1295 and tesamorelin.

How do micrograms convert to syringe units?

A U-100 insulin syringe has 100 units per millilitre, so units measure volume, not an amount of peptide. How much sermorelin each unit holds depends on how much liquid is in the vial.

For example, a 9 mg vial mixed with 9 mL holds 1,000 mcg per mL, so each unit holds 10 mcg and a 300 mcg dose is 30 units. Pharmacy premixed liquids differ: at 0.9 mg per mL, 300 mcg is 33 units; at 2 mg per mL, 10 units is 200 mcg. The same "20 units" can therefore mean anywhere from 180 to 400 mcg. [11], [34], [39] Doserly's reconstitution calculator works this out for any vial and shows each step.

Mix-ups are common. Users describe prescriptions written only in millilitres or "IU" with no microgram amount, and one pharmacy's syringe instruction that doubled a prescribed 150 mcg dose. [78], [79], [80]

What happens when you stop sermorelin?

No study has followed adults after stopping sermorelin. The adult studies ended with the last dose, and none looked for withdrawal effects or a rebound. That is missing data, not proof that nothing happens. [26], [25], [27]

Related data give context, not proof:

• Children. After a year of twice-daily injections, growth slowed below its usual pace for about 3 months, then returned to the rate before treatment. In another group, growth rates 6 months after stopping matched those before treatment, although 6 of 21 children kept growing faster. Antibodies to the drug had nearly disappeared 9 months after stopping. [72], [83], [48]
• A related medicine. In healthy men given tesamorelin for 2 weeks, IGF-1 went back to its starting level within 2 weeks of stopping. [84]

Allergic reactions can come back when people restart after a break, sometimes months later. See allergic reactions.

Personal accounts go both ways. Some people notice no change in sleep after stopping, or keep sleeping well for months; others describe sleep getting "horrible" about two weeks into a break, feeling "smaller and looser" after a month off, or an old shoulder pain returning after about two months. One user relayed that his doctor's patients had come off it without issue, losing the benefit gradually rather than all at once. Some claims online, such as "sermorelin shuts down your own growth hormone", have no evidence behind them. [85], [65], [86], [87], [59], [88], [89]

Does sermorelin work the same as an injection, troche or nasal spray?

Only injections and a research nasal spray have been measured. The approved product was a subcutaneous injection for treatment and an intravenous injection for the pituitary test, and even by subcutaneous injection only about 6% of the dose reaches the blood. [2]

Other forms are sold anyway: compounding pharmacies list 600 mcg troches that dissolve against the cheek, nasal sprays and clinic-prescribed tablets that dissolve under the tongue, some combined with ipamorelin. [35], [90], [91]

• Nasal spray. In healthy men, only 3–5% of a nasal dose reached the blood compared with an injection into a vein. In children with growth-hormone deficiency, a nasal version caused nasal irritation and antibodies and did not increase growth after 6 months. [92], [93]
• Troches and under-the-tongue tablets. No study has measured how much sermorelin they deliver. Peptides are normally broken down in the gut, so a swallowed or dissolved dose cannot be assumed to match an injection. One user's IGF-1 rose from 152 to 182 on a 0.75 mg troche, another's fell on a troche, and a woman who switched from injections to a tablet after an allergic reaction noticed no benefit over 4 months. [94], [87], [95]

How long does sermorelin last in the body?

Minutes. The US label gives a half-life of 11–12 minutes after either an intravenous or a subcutaneous injection, and the Irish label 6–7 minutes after an intravenous dose. In a 1994 study of 10 men, sermorelin disappeared from the blood with a half-time of about 4 minutes. [2], [24], [96]

After a subcutaneous injection, blood levels peak within 5–20 minutes. After the intravenous test dose, growth hormone peaked at about 30 minutes and stayed raised for about 2–3 hours. Enzymes in the blood, mainly one called DPP-4, cut the chain almost immediately. When an anti-doping laboratory tested a healthy 59-year-old man after a 500 mcg injection of a compounded product, intact sermorelin was undetectable at 30, 90 and 270 minutes; only a shortened fragment was found, at 30 minutes. [2], [24], [97], [98]

Doserly

What happens after one injection

Sermorelin in blood

After a subcutaneous injection, levels peak within 5–20 minutes and halve about every 11–12 minutes (US label). Only about 6% of the dose reaches the blood. In one volunteer given 500 mcg, intact sermorelin was already undetectable at 30 minutes.

Growth hormone

After the intravenous test dose, growth hormone peaked at about 30 minutes and was back near baseline within 2–3 hours.

IGF-1

Changes over days to weeks of use, not hours.

Curve shapes are schematic; timings come from the US and Irish Geref labels and a 2016 anti-doping study.

Sermorelin itself is gone within about an hour; any longer effect comes from the growth hormone and IGF-1 it releases.

You may see "10–20 minutes" quoted online; the primary figures run from about 4 to 12 minutes, depending on how it was measured. A very short half-life is not the same as a short effect: what matters afterwards is the growth hormone and IGF-1 it releases. Some pages also claim a steady level builds up with regular dosing, but a drug that is gone within an hour does not accumulate between nightly doses. [2], [96], [24]

Is sermorelin acetate different from sermorelin?

No. Sermorelin acetate is the same peptide in its salt form, which makes a stable powder; Geref was sermorelin acetate. Some products add other ingredients: users describe a pharmacy mix with glycine, and blends with ipamorelin or GHRP-2 and GHRP-6. [2], [99], [100]

Does the injection site matter?

The label said only to rotate injection sites. No study has compared sites. Stinging is common with some products, and two users traced burning to the mixing water or to alcohol still wet on the skin rather than to sermorelin itself. [2], [101], [102]

How should sermorelin be stored, and how long does it last?

The approved product had clear rules; today's compounded and research products mostly do not, and no study has measured how long mixed sermorelin keeps its strength.

• Powder, before mixing. Geref vials were kept in the fridge at 2–8 °C, and the Irish test product was also kept away from light. FDA extended the shelf life of the unopened, refrigerated diagnostic powder from 12 to 24 months in 1991, based on the maker's stability data. [2], [24], [103]
• After mixing. Both labels said to mix the powder with sterile saline just before use, inject it immediately and throw away what is left, and the US label added not to use a cloudy solution or one with particles. In water, sermorelin breaks down at two points in its chain into much weaker fragments, and it is most stable in slightly acidic conditions; the label's solution was mildly acidic (pH 5.0–5.5). [2], [24], [104]
• Compounded and research products. Websites give anywhere from 10–14 days to 4–6 weeks in the fridge after reconstitution, and one clinic page says 72 hours at room temperature is fine; none cites stability data. Compounded products carry a beyond-use date set by general pharmacy rules rather than sermorelin-specific testing, and users describe dates that conflict: 28 days after mixing from one pharmacy, "45 days from the time of dispensing" for a premixed liquid from another. [16], [12], [11], [33], [13], [105], [106], [107]

Premixed liquids are often shipped without cold packs. One supplier's handling sheet claims its product kept its strength after 7 days at 40 °C (104 °F), from an unpublished internal test, while users describe warm deliveries after 4–5 days in transit with no answer from the prescriber. Cloudy or clumpy vials after mixing are also reported, and one user who mixed a new pharmacy's vial with too little liquid, leaving it milky, went to the emergency room with swelling of the lips and throat. [108], [109], [110], [111]

This guide does not cover mixing or injection technique; the Academy note below covers practical handling.

What do we actually know about sermorelin in people?

More than for most peptides sold online, but little of it answers the questions adults ask today. The human research is a pituitary test, growth trials in children, three small studies in older men, and one placebo-controlled program in older men and women whose main results were never published in full.

What did the children's studies find?

In the study behind the 1997 approval, 110 children with growth-hormone deficiency were given 30 mcg per kilogram every night. Of 56 who could be evaluated at 12 months, average growth went from 4.1 cm a year before treatment to 8.0 cm a year at 6 months and 7.2 cm a year at 12 months. The other 54 were not counted: 24 did not meet the entry criteria, 10 met the rules for stopping and 20 had not responded well enough by 6 months. The study had no comparison group. [2], [112]

• Longer use. In 16 children given one nightly injection for 12–24 months, 11 responded, growing about 6.5 cm a year throughout. [113]
• Against growth hormone. In a randomized study of 60 children, those on sermorelin grew 9.2–9.3 cm a year and those on growth hormone 14.6 cm a year. Another randomized study of 43 children found that only growth hormone improved height compared with bone age. Children who did not respond to Geref generally did well when switched to growth hormone. [48], [49], [114]
• What was never shown. The label says its effect beyond one year and on final adult height "remains to be determined", and the recommended dose was never compared directly with growth hormone at its recommended dose. [2], [4]

That is why sermorelin cannot make an adult taller: height gain happens at the growth plates, and the label said to stop treatment once they closed. [2]

What did the adult studies find?

Doserly

What the longest placebo-controlled sermorelin trials found

IGF-1: rose

About 40% in men and 30% in women not taking estrogen, but under 10% in women on oral estrogen; about 35% overall.

Body fat and lean mass: shifted slightly

Body fat fell about 5% with a matching gain in lean mass; smaller in women on estrogen.

Strength: no improvement

No improvement compared with placebo.

Aerobic fitness: no improvement

No improvement compared with placebo.

Physical-function score: no gain

Stable on sermorelin while it fell on placebo; it did not improve.

Sleep questionnaire (PSQI): slightly worse

Score rose from 4.1 to 5.41 on sermorelin (37 people) vs 4.51 to 4.61 on placebo (38); a higher score means worse sleep.

Thinking tests: several improved

Better scores on several thinking and problem-solving tests after 6 months (89 adults, published 2006).

About 1 mg (14 mcg/kg) each evening for 5–6 months in healthy older adults; preliminary figures reported by the investigators. Filled marker: changed; grey dash: no improvement; amber: worse.

Hormone levels and body composition moved; function and sleep did not.

Beyond single test doses, sermorelin has been given to healthy adults in only two small studies of older men and one placebo-controlled program in older men and women. No study has tested it in younger adults, in women on today's hormone therapy, or with the schedules clinics use. [25], [26], [46]

Which trials were registered?

No registered trial names sermorelin as its drug. The University of Washington sleep trial is registered under "GHRH"; its investigators and the NIH grant records identify the drug as Geref. Status checked September 24, 2026:

A search of European, UK and Australian–New Zealand trial registries found no sermorelin trials. [117], [118]

Is the popular "adult sermorelin study" really about sermorelin?

No. The study most often quoted online, 19 adults aged 55–71 given 10 mcg per kilogram nightly for 16 weeks, used a modified GHRH with one amino acid swapped ([Nle27]GHRH(1-29)). It found higher growth hormone and IGF-1, thicker skin, and better lean mass and insulin sensitivity in men only, with sleep quality unaffected. Those results belong to that molecule, not to sermorelin. [51], [52]

What do the sleep studies show?

The sleep laboratory studies behind many sleep claims gave GHRH as quick injections into a vein during the night, and their summaries do not say whether they used the 29- or the 44-amino-acid form. Their results depend heavily on conditions:

• In young men, night-time injections increased deep (slow-wave) sleep in some studies, especially when given later in the night, but not in another study that gave GHRH before or at sleep onset; after sleep loss, injections reduced time awake. [119], [120], [121]
• The effect was much smaller in older people, even after 2 weeks of "priming" doses. [122], [123]
• A steady infusion, or a dose in the early morning, had no sleep effect. [124], [125]
• In young women, the same kind of injections made sleep worse. [126], [127]
• A 300 mcg nasal dose increased deep and dreaming sleep in the second half of the night in young and older men. [128]

None of these used a bedtime subcutaneous injection of sermorelin, and the one trial that did, in older adults, found no improvement. A 2003 review of the research on aging concluded that long-term treatment with short-acting GHRH did not improve sleep. [27], [129]

Does raising IGF-1 mean better health?

Not automatically. Growth hormone, an IGF-1 number, body composition, strength and how someone feels are different outcomes. In sermorelin's longest trials, IGF-1 and body composition changed while strength, fitness and sleep did not, and nothing is known about effects on heart disease, fractures or lifespan. [28], [129]

How does sermorelin work?

Growth hormone is released in bursts through the day and night, with the largest usually early in sleep. GHRH from the hypothalamus drives each burst, and a second hormone, somatostatin, acts as the brake between them. Growth hormone then prompts the liver and other tissues to make IGF-1. Sermorelin binds the same GHRH receptors on the pituitary's growth-hormone-making cells, so it pushes the "release" side of that system. [2], [130]

The effect is selective. In 5 healthy men, intravenous sermorelin raised growth hormone without changing prolactin, thyroid, reproductive or stress hormones, insulin or blood sugar. Larger doses mainly make the growth-hormone release last longer rather than peak higher. [131], [132], [133]

Why does it need a working pituitary?

Because sermorelin only asks the pituitary to release growth hormone, it does nothing if the pituitary cannot respond. The label excluded children whose pituitary did not respond to a Geref test, and the Irish label notes that obesity, high blood sugar, an underactive thyroid and somatostatin blunt the response. After radiation to the head, the response is weaker. [2], [24], [134]

Does the body get used to it?

The evidence points both ways. After a 10-hour drip of GHRH, 4 men released less growth hormone to a later test dose, and children on a continuous subcutaneous infusion showed a rise, then a decline over 3–6 months. In cells, the receptor stops responding within hours of constant exposure. [135], [68], [69]

On the other hand, children on one nightly injection kept growing faster for up to 2 years, and a continuous infusion of a related GHRH did not lose its effect over 8 days in men. No study has tested whether nightly adult use fades over months, or whether breaks restore it. Some users report weaker effects in their second course. [113], [136], [137]

Is sermorelin "natural", and does the body's brake keep it safe?

Sermorelin is synthetic, although its chain matches part of the human hormone. The body's brake, somatostatin, keeps working while it is used, but that does not cap the dose: higher exposure raised baseline growth hormone in children and twice-daily injections raised blood sugar and insulin. The claim that feedback makes overdose "impossible" is not supported. [2], [71], [72], [70]

What are the risks and unanswered questions?

Is sermorelin safe?

In short courses under medical supervision, it caused mostly mild problems, but its safety over months in adults has never been properly studied, and allergic reactions are a real risk. The children's trials and small adult studies found mostly injection-site reactions, while personal accounts and FDA reports describe allergic reactions that the trials did not capture. [2], [25], [26], [138]

What side effects did the label and studies report?

In children's trials, the most common side effect was an injection-site reaction (pain, swelling or redness) in about 1 in 6; 3 of 350 children stopped because of it. Headache, flushing, difficulty swallowing, dizziness, hyperactivity, sleepiness and hives each affected fewer than 1%. [2], [29]

• The intravenous test occasionally caused facial flushing, nausea, vomiting, a strange taste, paleness and chest tightness. [2], [24]
• Antibodies to the drug were common: in 39 of 40 children in one study and 6 of 11 at 12 months in another. They did not appear to affect growth and had nearly disappeared 9 months after stopping, and the label says no generalized allergic reactions were reported in its trials. [48], [113], [2]
• In older adults, the short studies found no significant side effects, and the investigators of the longer trials described leg swelling and joint pain as "very uncommon". [25], [26], [27]

Can sermorelin cause an allergic reaction?

Yes, and the pattern people describe is easy to miss. The label warns that local or whole-body allergic reactions may occur and that prompt medical attention is needed. FDA's adverse-event database holds 61 reports naming sermorelin through July 2026, 32 of them as a suspected cause; 15 of those 32 involve allergic or skin reactions, including 4 describing anaphylaxis (two may describe the same event) and a hospital stay for fainting with low blood pressure and flushing. These are unverified reports, not rates. [2], [138]

Public accounts describe a consistent course, usually after weeks or months without problems:

• Itchy injection sites first. Red, itchy welts that last days, often starting around weeks 4–12, sometimes after 5–12 months. [139], [140], [141]
• Then a fast, whole-body reaction within minutes of a dose: itchy or burning palms and soles, flushing, hives, a racing heart and, in some accounts, fainting or collapse. One person's heart rate went from 63 to 118. [142], [66], [143], [141]
• Old injection sites flare at the same time. [144], [139]
• It comes back on restarting, even after 3–6 months off or with a different seller's product, and lowering the dose did not stop it for some people. [66], [141], [140]
• It can spread to related peptides. Several people then reacted to CJC-1295, a modified GRF or ipamorelin. [145], [141], [66] In community education groups, members describe the same with tesamorelin, though some tolerated ipamorelin alone.

The most serious accounts include a physician-confirmed anaphylaxis with throat tightening and wheezing in someone who had reacted to CJC-1295 before, and an emergency visit for swelling of the lips, mouth and throat after an over-concentrated, milky vial. Two clinic or pharmacy staff members described the same sudden reactions in several patients, with product from at least three pharmacies. [146], [111], [141]

Why this happens is not known. In rat cells in a dish, sermorelin released histamine, the chemical behind hives and itching, and product impurities are another possible trigger. [147], [148] Hives, swelling of the lips, face, tongue or throat, wheezing, trouble breathing, vomiting or fainting after an injection need urgent medical care. The label of tesamorelin, an approved GHRH medicine, tells people with signs of an allergic reaction to stop it and get prompt medical attention. [149]

Can it cause flushing, a racing heart or chest symptoms?

Flushing affected fewer than 1% of children in trials but is reported far more often by adults, usually a warm face or head rush for 5–20 minutes after injecting; some notice none. More worrying accounts come mostly from blends. [2], [150], [151], [75]

In week 3 of 300 mcg of sermorelin plus 300 mcg of ipamorelin, one person had palpitations, an odd feeling in the chest and tingling in the left arm, with normal blood tests and heart tracing; the symptoms stopped after cutting to 150 mcg, and another user had the same experience. A first 200 mcg dose raised another person's heart rate enough to keep them awake. [59], [152] Chest pain or pressure, or a racing heart that does not settle, needs prompt medical assessment.

Does it cause hunger, water retention or joint pain?

The label lists none of these, and the older-adult trials called swelling and joint pain very uncommon. Labels for growth hormone itself list fluid retention, joint pain and nerve compression such as carpal tunnel syndrome. [2], [27], [153]

Personal accounts describe all three, often alongside other drugs. A prescriber on a forum said about three of his patients stopped because of uncomfortable hunger, and a user on low-dose tirzepatide described hunger "through the roof" on 400–600 mcg. Others describe water retention and sore hips, old sports injuries flaring with dizzy spells, and elbow and wrist pain on a sermorelin and GHRP-2 blend that lasted a month after stopping. FDA's ipamorelin review records elbow pain in a man using a compounded ipamorelin and sermorelin product. [154], [155], [156], [157], [158], [31]

Does sermorelin affect blood sugar?

Not in the short adult studies, which found no change in fasting blood sugar or insulin over 2–6 weeks. But in children with short stature, twice-daily injections for a year raised fasting blood sugar and insulin, and a longer-acting form of GHRH impaired glucose handling in older adults. Labels for growth hormone and tesamorelin require blood-sugar checks. [25], [26], [72], [159], [153], [149]

Can it affect the thyroid?

Possibly. During the children's trials, 6.5% developed an underactive thyroid (hypothyroidism): 8 of 110 children in the largest study were already on thyroid medicine and 5 more needed it after starting. Children with growth-hormone deficiency have a higher background risk, so the drug's role is uncertain, but the label required thyroid tests before and during treatment because an underactive thyroid blunts the response. [2]

What other effects do people report?

Single or occasional reports include acne, hair shedding, loss of taste, vivid dreams or hallucinations in the first nights, a feeling of "forgetting how to breathe" while falling asleep, running out of energy early on long fasted runs, and hours of severe abdominal cramping during an allergic reaction in a woman using hormone pellets. Causes are unclear, and some posters later doubted their own attribution. [160], [161], [162], [145], [163], [164], [165], [166], [139] In community education groups, two women on hormone therapy describe cramps after each dose of a sermorelin and ipamorelin blend.

Does sermorelin cause cancer?

Nobody knows. The label notes that no long-term animal studies for cancer (carcinogenicity) were done, and there are no long-term data in adults. Growth-hormone medicines carry warnings about tumors, and the labels of growth hormone and tesamorelin list active cancer as a reason not to use them. [2], [153], [149]

Could product quality change the risk?

Yes. In 2022 a compounding pharmacy recalled two lots of 9 mg sermorelin vials that were out of specification, and in 2024 FDA warned a seller offering "SERMORELIN" as a research product. A Belgian laboratory found chemical changes and widely varying amounts in illegally sold peptides including sermorelin, and falsified injectables seized in Europe in 2014 included it. A 2026 analysis of consumer lab reports found sermorelin had the lowest median measured amount of the 14 peptides tested, 97.45% of the label claim, and one of the highest rates of failing on both amount and purity; it is a preprint and has not been peer reviewed. [167], [168], [148], [169], [170]

Is sermorelin legal? Is it FDA-approved?

Checked September 24, 2026. Rules differ by country and change quickly.

United States. No approved sermorelin product is marketed.

• 1990 and 1997. FDA approved Geref for the pituitary test (December 1990) and for children with growth-hormone deficiency (September 1997). [5], [6], [171]
• 2008–2009. The maker discontinued both products in 2008; FDA withdrew approval effective June 18, 2009. [3]
• 2013. FDA determined the products were not withdrawn for safety or effectiveness reasons, which would allow a generic version; none is marketed. [3], [172]
• Compounding today. FDA's list of bulk substances nominated for outsourcing facilities places sermorelin acetate in the group under evaluation and marks it as a component of FDA-approved drugs, and federal rules let pharmacies compound components of approved drugs on prescription. Unlike CJC-1295 and ipamorelin, it is not on FDA's list of compounding substances that may present significant safety risks. Compounded drugs are still not FDA-approved or reviewed before sale. [8], [173], [174], [9]
• 2024. FDA warned a seller whose sermorelin was labelled "for research use only" that its products were unapproved new drugs intended for human use: a research-use label does not make a product legal to sell for people. [168]

Canada. Sermorelin is on Health Canada's Prescription Drug List, but no sermorelin product is authorized for sale, and Health Canada included it in a 2025 advisory about unauthorized injectable peptides seized from a seller. [175], [176], [177]

Australia. Sermorelin is a prescription-only medicine (Schedule 4), and no product is registered with the TGA. [178], [179]

Europe and the United Kingdom. Ireland authorized the Geref 50 test in 1991 and withdrew it in 2007. We found no current sermorelin product in the EU's central register or the UK's medicines database. [180], [179]

Is sermorelin banned in sport? Does it show up on a drug test?

Yes, it is banned. The World Anti-Doping Agency names sermorelin among growth-hormone-releasing factors prohibited at all times in its 2026 and 2027 lists, and USADA says a therapeutic use exemption is "highly unlikely" to be approved. Anti-doping laboratories can detect sermorelin and its breakdown fragment in blood and urine, although intact sermorelin cleared from one volunteer's blood within 30 minutes. [23], [181], [41], [98], [182]

Who should be especially cautious?

These groups have no safety data for sermorelin. That is a reason for caution, not proof of harm.

• Anyone who has reacted to a peptide injection before, especially to CJC-1295, ipamorelin or tesamorelin. [146], [141]
• Pregnancy and breastfeeding. The label rated it pregnancy category C after minor fetal changes in rats and rabbits, and it is not known whether it passes into breast milk. The Irish label said not to use it in pregnancy or breastfeeding. [2], [24]
• Cancer, diabetes or diabetic eye disease. There are no data, and related labels list active cancer as a reason not to use them and warn about blood sugar and diabetic eye disease. [153], [149]
• Thyroid disease, because of the label's thyroid findings. [2]
• A pituitary or brain tumor, or a growth-hormone problem caused by one: the label says such patients were not studied and should not be treated with it. [2]
• Epilepsy. The Irish label advised caution. [24]
• Under 18. The children's approval was for a diagnosed deficiency under specialist care; this guide is written for adults.
• Competitive athletes. It is banned at all times.
• People taking other medicines. See the next question.

Has sermorelin been tested alongside other medicines?

Only in the context of the label. It says steroid medicines such as prednisone (glucocorticoids) may blunt the response and that formal interaction studies were never done; the Irish label adds that somatostatin-type drugs, insulin, aspirin and similar pain relievers, some bladder and stomach medicines (antimuscarinics) and antithyroid drugs can distort the test result. It has not been tested with testosterone, GLP-1 medicines or other peptides, although most personal accounts combine it with at least one. Bring a complete list of everything you take to a pharmacist or doctor. [2], [24]

What should be monitored while using sermorelin?

There is no current monitoring plan for adults, because no approved sermorelin product exists today. What exists is what the old label required for children, what the adult studies measured, and what labels for related medicines ask for. It can help you prepare questions for a clinician; it is not a personal testing plan.

What did the approved label require?

• Thyroid tests before starting and throughout treatment, because an underactive thyroid developed in 6.5% of children and blunts the response. [2]
• Growth checks: height at least every 6 months and bone age from time to time, with a switch to growth hormone for children whose response was poor or fading. [2]
• Blood tests that may rise: phosphorus, alkaline phosphatase, growth hormone and IGF-1. [2]

What did the adult studies measure?

The 1992 study tracked 24-hour growth hormone, IGF-1, fasting blood sugar, blood pressure and routine blood tests; the 1997 study added a glucose tolerance test, cholesterol, a body-composition scan and strength tests; and the University of Washington trials measured IGF-1, body composition, strength, physical function, sleep and thinking tests. Blood sugar, blood pressure and routine tests did not change in the short studies. Children's studies also checked antibodies, blood sugar and, in one group treated after radiation, blood counts, cholesterol and thyroid function every 3 months. [25], [26], [27], [183]

What do labels for related medicines ask for?

These are class-based considerations from approved medicines that also raise growth hormone, not sermorelin findings.

• Tesamorelin, an approved GHRH medicine: check IGF-1 and consider stopping if it stays very high; check blood sugar before and during treatment, and the eyes of people with diabetes; watch for swelling, joint pain and allergic reactions. In its trials, 5% of patients developed blood sugar in the diabetes range (an HbA1c, a three-month average, of 6.5% or higher), compared with 1% on placebo. [149]
• Growth hormone itself (somatropin): periodic blood sugar and thyroid checks, an eye check for raised pressure in the skull before starting, and watching existing moles for changes. [153]

Which signals matter, and why?

Every row comes from the label, the studies, FDA reports or related labels cited above, except hunger, which comes only from personal accounts. [2], [25], [27], [138], [149], [153]

A single IGF-1 result is hard to read without a starting value, and it can move for other reasons: oral estrogen blunted the rise in the placebo-controlled trials, and eating in a calorie deficit or other drugs can change it too. Some clinics adjust the dose by an IGF-1 test at 6–8 weeks. [27], [19] In community education groups, educators commonly advise testing IGF-1, fasting insulin and HbA1c before starting and again after 6–12 weeks, but few members report doing it. See what people report about IGF-1.

What do people in public communities report?

Most public accounts we reviewed come from adults who get sermorelin through a clinic or telehealth prescription or from research vendors, and almost all are also taking testosterone, menopause hormone therapy, a GLP-1 medicine, ipamorelin or other peptides. The accounts below cannot separate what sermorelin did from everything else.

What do the positive reports look like?

Better sleep is by far the most common. People describe deeper, unbroken sleep and vivid dreams, often within the first week: "some of the best nights of sleep I've ever had" in week one, dreaming by week one and restful sleep by month one on 200 mcg five nights a week, and "sleep is amazing" after 4 months at 200 mcg. One person with insomnia was able to halve a prescribed sleep medicine. [184], [185], [186], [187]

Other positive reports describe faster recovery from training (sore for about a day instead of 2–3), more energy and, over months, a slightly leaner build. The body changes almost always come with dieting, training, testosterone or a GLP-1 medicine; one person lost 18 lb over 4 months while their doctor also prescribed tirzepatide, and another said sermorelin helped their build but not their belly fat. [188], [189], [190], [191]

How long does it take, according to these accounts?

Sleep changes are usually described within the first nights to 2 weeks, while body changes are described over 2–6 months. One person said it took about 3 months to feel the full effect, and another person's doctor said two or three courses may be needed. [185], [65], [188], [192] In community education groups, educators say visible change, if any, comes at around 5–12 weeks.

Does everyone respond? What happens to IGF-1?

No. Nonresponse is common: "I haven't felt or noticed any change" after 4 months of 200 mcg; "4 months didn't do anything"; "My IGF numbers barely moved" after 3 months. [193], [194], [195]

IGF-1 results go both ways:

• Rises: 81 to 159 ng/mL after 4 months; from below the lab's range to mid-range after about 6 months; 152 to 182 on a troche. [196], [65], [94]
• Little or no rise: 108 to 138 after 4 months at 1,000 mcg nightly; 211 after 6 months at 500 mcg on testosterone. A 67-year-old concluded after 6 months at 1,000 mcg that it did not work for him, and his IGF-1 rose from 99 to 160 only after ipamorelin was added. [197], [198], [199]
• Falls: 154 to 134 after 9 months on testosterone despite feeling better; lower after 3 months at 1,000 mcg; 246 to 114 on sermorelin and ipamorelin during a long calorie deficit. [200], [201], [202]

Many of these numbers have no proper starting value, were taken at different times, or come from people eating in a deficit or changing hormone doses. A common path is to try sermorelin first and later move to CJC-1295 and ipamorelin, tesamorelin or growth hormone for a stronger effect; others prefer sermorelin because it causes fewer side effects. [87], [45], [203], [151]

Can it make sleep worse?

Yes, for some. Accounts describe deep and REM sleep on a wearable dropping from 1–2 hours to under 45 minutes each; great sleep for a month, then "the worst it's ever been" on injection nights from month two; being unable to sleep in, waking at about 5:30 every day; and months of waking every 2–3 hours, with one person nearly falling asleep while driving. [204], [205], [206], [207]

Others sleep deeply but wake groggy, feeling "drugged". One person's grogginess went away when a new vial of lower strength cut the dose at the same syringe mark, and several people who slept worse did better on a lower dose or a morning dose. [208], [209], [66], [58]

What unwanted effects come up?

Stinging, bruising or itching at the injection site is common, often early and sometimes settling within a couple of weeks. [187], [210], [102] The other effects people describe, including flushing, a racing heart, hunger, water retention, joint pain and delayed allergic reactions, are covered with the study data in the risks section; most of the more worrying accounts involve blends with ipamorelin or other peptides. [75], [59], [211], [212]

What about people on testosterone, menopause hormone therapy or GLP-1 medicines?

Many men on testosterone describe sermorelin as adding little: "negligible", or "okay, but it's expensive" after two years. Women on menopause hormone therapy describe better deep sleep over two 3-month rounds but no change in skin or muscle, or "amazing sleep" and more energy by 6 weeks. [77], [213], [214], [215]

People on GLP-1 medicines report both sides: one gained 7 lb in 3 weeks after adding it to semaglutide and slept worse in the first week, another found it fixed insomnia they had on tirzepatide. [216], [87] In community education groups, many of the detailed accounts come from middle-aged and older women taking a GLP-1 medicine, often with hormone therapy.

How can you judge a sermorelin story?

Useful questions to ask: What was the dose in micrograms, not just units or millilitres, and was it from a pharmacy or a research vial? Was ipamorelin or another peptide in the same syringe? What else started or changed: testosterone, estrogen, a GLP-1 medicine, diet or training? Was there an IGF-1 result from before, taken the same way? Did they post an update weeks later? Follow-ups often change the story, especially for sleep and for allergic reactions.

These selected discussions help identify questions and experiences that research should examine. They are not a survey of all users, a response rate or a substitute for controlled human studies.

How does sermorelin compare with CJC-1295, tesamorelin, ipamorelin and growth hormone?

CJC-1295 and tesamorelin are other lab-made versions of GHRH, ipamorelin is the peptide most often paired with sermorelin, and growth hormone is what all of them aim to raise.

The real differences are how long each lasts, how much is known and where it stands legally. Sermorelin and tesamorelin last minutes, ipamorelin about 2 hours and the hooked CJC-1295 about a week. Tesamorelin is the only one of the peptides approved today; sermorelin was approved in the past, and unlike CJC-1295 and ipamorelin it is not on FDA's list of compounding substances with significant safety risks. Growth hormone supplies the hormone directly and does not need a working pituitary. No study has compared sermorelin with the other peptides in adults, so the table cannot say which works better. See also the Doserly guides to MK-677, an oral drug that also raises growth hormone, and the CJC-1295 and ipamorelin blend.

Common questions about sermorelin

Is sermorelin FDA-approved?

Not today. FDA approved it as Geref for a pituitary test in 1990 and for children with growth-hormone deficiency in 1997, but the maker discontinued it in 2008 for business reasons and no approved product has been sold since. What clinics prescribe now is compounded by pharmacies, which FDA does not review before sale, and "research" vials are unapproved drugs. [3], [7], [9] See the dated legal-status summary.

How long does sermorelin take to work?

In the intravenous test, growth hormone peaked about 30 minutes after the dose, but how long it takes to feel or see anything is not known from studies. People usually describe sleep changes within the first nights to 2 weeks and body changes over months, and many notice nothing. In the placebo-controlled trials, IGF-1 and body composition had changed after 5–6 months, while sleep had not improved. [24], [27], [185] See what people report.

Is sermorelin the same as HGH? Is it a steroid?

Neither. Sermorelin is a peptide that prompts the pituitary to release the body's own growth hormone (HGH), so it only works if the pituitary can respond; growth hormone itself is a prescription medicine that supplies the hormone directly. Anabolic steroids are a different kind of molecule that act on hormone receptors. All three are banned in sport. [2], [23] See how it compares.

Can sermorelin make you taller?

Not in adults. Height grows at the growth plates near the ends of the long bones, which close after puberty. Geref was approved only for young children who had not reached puberty and whose growth was slowed by growth-hormone deficiency, and the label said to stop it once the growth plates closed. Even in those children, growth hormone worked better. [2], [48] See the children's studies.

Should sermorelin be taken with ipamorelin?

Many clinics and users pair them, on the reasoning that the two act on different receptors and release more growth hormone together. That reasoning comes from single intravenous tests of related peptides; sermorelin and ipamorelin together have never been tested, and a second peptide adds its own side effects and makes any reaction harder to trace. Several people who reacted to one later reacted to the other. [73], [74], [141] Read the ipamorelin guide.

Is sermorelin weaker than tesamorelin or CJC-1295?

Nobody has compared them in a study. Sermorelin lasts minutes and only about 6% of an injected dose reaches the blood, and in personal accounts many people describe it as the mildest option and later switch to tesamorelin or CJC-1295 with ipamorelin for a stronger effect; one person who used both could not tell it apart from tesamorelin, and others prefer it for its milder side effects. Mild does not mean safer: it carries its own risk of allergic reactions. [2], [87], [221], [151] See how they compare.

Can you take sermorelin with semaglutide or tirzepatide?

Many people do, often hoping to protect muscle while losing weight, and some doctors prescribe them together. The combination has never been studied. Accounts include weight gain and worse sleep after adding sermorelin to semaglutide, hunger on tirzepatide and, for others, better sleep. People taking GLP-1 medicines, which slow digestion, often wait longer after eating before a dose. [190], [216], [155], [87] See interactions.

Has sermorelin been studied in women?

Yes, in the University of Washington trials, which included older women taking and not taking estrogen. IGF-1 rose about 30% in women not taking estrogen but under 10% in those taking oral estrogen, and the body-composition change was smaller. In young women, night-time GHRH injections into a vein made sleep worse in a sleep laboratory study. There are no data on pregnancy or on today's menopause hormone therapy. [27], [126], [2]

Glossary

Plain explanations of the route, dosing and research terms used in this guide. Underlined terms in the text link here.

Adverse event

A harmful or unwanted medical event reported after someone used a treatment. A report alone does not prove the treatment caused it.

Amino acid

A small chemical building block. Chains of amino acids make up peptides and proteins.

Anaphylaxis

A severe, fast allergic reaction that can include hives, swelling of the face or throat, trouble breathing and a drop in blood pressure. It needs emergency care.

Animal study

Research in animals such as rats or monkeys. It shows what a substance does in a living body, but results in people can differ.

Antibodies

Proteins the immune system makes against something it sees as foreign. Children treated with sermorelin often made antibodies to it; in the trials these did not seem to affect growth.

Beyond-use date

The date after which a pharmacy-made (compounded) product should not be used. It is set by general pharmacy rules, not by testing of each drug.

Bioavailability

The share of a dose that reaches the bloodstream. After a subcutaneous injection, only about 6% of a sermorelin dose did.

Blend

A product that combines sermorelin with another peptide, such as ipamorelin. The blend's total amount is not its sermorelin amount.

Carcinogenicity study

A long-term animal study designed to detect whether a substance can cause cancer. None was done for sermorelin.

Carpal tunnel syndrome

Numbness, tingling or pain in the hand caused by pressure on a nerve at the wrist. Fluid retention can bring it on.

Cell study (in vitro)

Research on cells grown in a dish. It gives early clues about biology, but it is far from proof of benefit in people.

Compounding

When a pharmacy prepares a medicine from individual ingredients for a prescription. Compounded drugs are not FDA-approved or reviewed before sale.

Controlled trial

A study that compares people who receive a treatment with a similar group who do not, often receiving a placebo instead. Randomly assigning people to each group makes the comparison fairer.

Course and cycle

A course is the period of repeated use, such as 3 months. A cycle is a course plus a planned break before any further use.

Daily total

All the amounts given in one day, added together. For example, 0.5 mg twice daily is a 1 mg daily total.

Dose (amount each time)

The amount given on one occasion. A protocol lists both the dose and how often it is given.

DPP-4

Dipeptidyl peptidase-4, an enzyme in the blood that cuts the first two amino acids off sermorelin and helps explain why it lasts only minutes.

Freeze-dried (lyophilized)

Dried by freezing and removing the water, leaving a powder. Sermorelin is sold this way and mixed with liquid before injection.

GHRH

Growth-hormone-releasing hormone, the brain's own signal telling the pituitary to release growth hormone. Sermorelin copies its first 29 amino acids; CJC-1295 and tesamorelin are other lab-made versions.

Growth hormone (GH)

A hormone released in pulses by the pituitary gland. It affects growth, metabolism and body composition, and prompts the body to make IGF-1.

Growth plate

A band of cartilage near the end of a child's long bones where growth in height happens. The plates close after puberty, after which height cannot increase.

Growth-hormone deficiency

A condition in which the pituitary releases too little growth hormone. In children it slows growth; Geref was approved for children whose deficiency had no known cause and whose pituitary could still respond to it.

Half-life

The time it takes for the measured level of a substance in the blood to fall by half. It is not the same as how long an effect lasts.

Hypersensitivity (allergic reaction)

An immune reaction to a substance, from itching and hives at an injection site to a whole-body reaction. With sermorelin, reactions have been described after weeks or months of use.

Hypothalamus

A small region at the base of the brain that controls the pituitary gland, including by releasing GHRH and somatostatin.

Hypothyroidism

An underactive thyroid gland. It developed in 6.5% of children during sermorelin trials and can blunt the response to it.

IGF-1

Insulin-like growth factor 1, a hormone made mainly in response to growth hormone. A blood test for IGF-1 is the usual way to check growth-hormone activity.

Intranasal

Given as a spray into the nose. Only a small share of a nasal sermorelin dose reached the blood.

Intravenous (IV)

Injected into a vein. The approved sermorelin test was given this way.

Ipamorelin

A lab-made peptide that releases growth hormone through the ghrelin receptor, a different switch from the one sermorelin uses. It is often paired with sermorelin.

Label (prescribing information)

The official document approved with a medicine, giving its uses, doses, warnings and storage. Sermorelin's US label dates from its time as Geref.

mcg and mg

Micrograms and milligrams. 1 mg equals 1,000 mcg, so 0.3 mg is 300 mcg.

mcg per kg

Micrograms per kilogram of body weight. The children's label dosed this way: 30 mcg per kg is 900 mcg for a 30 kg child.

Oral, troche and sublingual

Taken by mouth. A troche dissolves against the cheek and a sublingual tablet under the tongue. No study has measured how much sermorelin these forms deliver.

Peptide

A short chain of amino acids. Sermorelin is a chain of 29.

Pharmacokinetics

How the body absorbs, moves, breaks down and removes a substance.

Pituitary gland

A pea-sized gland at the base of the brain that releases growth hormone and several other hormones.

Placebo

A dummy treatment with no active ingredient, used as a comparison in studies.

Preclinical research

Studies done before or alongside research in people: cell studies and animal studies.

Reconstitution

Mixing a freeze-dried powder with a liquid so it can be measured and injected. The amount of liquid sets how much peptide each unit holds.

Research use only

A label on products sold for laboratory research. It does not mean a product is approved, tested for human use or legal to sell as a medicine.

Schedule 4 (Australia)

Australia's prescription-only medicine category.

Secretagogue

A substance that makes a gland release a hormone. A growth hormone secretagogue makes the pituitary release growth hormone rather than supplying it.

Slow-wave (deep) sleep

The deepest stage of sleep, when the body's largest growth-hormone release usually happens.

Somatostatin

A hormone from the hypothalamus that acts as the brake on growth-hormone release between pulses.

Stimulation test

A test that gives a substance to see whether the pituitary can release growth hormone. Geref was approved as one.

Subcutaneous (SC)

Injected into the fatty layer just under the skin. The approved treatment and the adult studies used this route.

Syringe units

Markings on an insulin syringe that measure volume. On a U-100 syringe, 100 units equal 1 mL. The amount of drug per unit depends on the vial's concentration.

Tesamorelin

An FDA-approved, lab-made version of GHRH used to reduce excess abdominal fat in adults with HIV and lipodystrophy.

Titration

Adjusting a dose in steps, usually starting lower and increasing if needed.

WADA

The World Anti-Doping Agency, which publishes the list of substances banned in sport.

Withdrawal and rebound

Withdrawal effects are symptoms caused by stopping a substance. A rebound is a problem returning worse than before after stopping. Neither has been studied for sermorelin.

Explore more of the research

Go deeper into the laboratory and animal studies behind the claims. Sermorelin's preclinical record is small and mostly about how the body clears it; there is no tissue-repair or longevity research on sermorelin itself.

How this guide was researched

This guide is built from a thorough review of the sources cited throughout it: published scientific studies, the historical approved label, registered clinical trials, regulatory documents and published protocol descriptions. We also reviewed public online forums and community education groups where people describe their own experiences with sermorelin.

The guide cites 230 sources, including 61 original scientific papers: 42 human studies, 10 cell, animal and computer studies and 9 laboratory and product-testing studies. Many of the human studies tested GHRH of an unstated form, related molecules or other peptides rather than sermorelin itself, and are labelled that way. We have not padded that count. Each type of source answers a different question. Studies show what researchers measured. Protocol descriptions show how sermorelin is typically used. Personal accounts show what individual people experienced. Every numbered citation links to its entry below, labeled by source type.

How this guide was made

Research and drafting were AI-assisted. Every cited source was checked against the original, and the guide was reviewed and edited by Doserly before publication. It has not had an independent clinical review, and Doserly does not currently have medical reviewers. Doserly makes a medication and health-tracking app and runs Doserly Academy, both of which are promoted in this guide. Read our editorial policy for how guides are researched, updated and corrected.

This guide is for educational purposes. It summarizes what the reviewed sources report so the research is easier to understand; it is not medical advice. For a deeper dive, or to check any point for yourself, go straight to the cited sources.

Explore the sources