Tesofensine: The Definitive Guide

What is tesofensine?

Tesofensine is an experimental weight-loss drug taken as a tablet once a day. It acts in the brain, where it reduces appetite, and as of September 2026 it is not approved as a medicine in any country. [1], [2], [3]

It is a small lab-made molecule, not a peptide (a chain of amino acids), even though many peptide sellers list it. Chemically it belongs to the tropane family, with the formula C17H23Cl2NO and a molecular weight of about 328. In research papers it also appears under its development code, NS-2330. [4], [5]

Tesofensine is a reuptake inhibitor. Nerve cells pass signals using chemical messengers called neurotransmitters, then pull the messengers back in to reuse them. Tesofensine blocks that recycling for three of them: dopamine, noradrenaline (also called norepinephrine) and serotonin, so more of each stays active between nerve cells. That is the likely basis of its effect on hunger, and also why it can raise heart rate, disturb sleep and change mood. [1], [6], [7]

It started as a brain drug. The Danish company NeuroSearch and Boehringer Ingelheim tested it in Parkinson's disease and Alzheimer's disease; it did not help either condition, but patients lost weight, so it was redeveloped for obesity. The Danish company Saniona now owns it, and its partner Productos Medix holds the rights in Mexico and Argentina. [8], [9], [10], [11], [2]

The key word is investigational: it has been tested in people, including a completed phase 3 trial, but no regulator has approved it. Medix applied for approval in Mexico, where the regulator withheld approval in November 2024; the company was still pursuing approval in August 2026. A separate product, Tesomet, combines tesofensine with the heart medicine metoprolol and is being developed for two rare causes of obesity. [12], [3], [13], [2], [14], [15], [16]

Timeline of tesofensine from 2004 to 2026. Parkinson's and Alzheimer's trials from 2004 to 2008 showed no benefit but weight loss; the TIPO-1 obesity trial was published in 2008 and received an expression of concern in 2013; a 372-person Mexican phase 3 trial reported top-line results in December 2018. Medix applied for approval in Mexico at the end of 2019; the FDA granted orphan designations for Tesomet in 2021, which are not approvals; a Mexican committee gave a favorable, non-binding opinion in February 2023; Mexico withheld approval in November 2024; in 2025 WADA listed it as a stimulant and Medix planned to resubmit; in December 2025 an FDA warning letter listed it as ineligible for compounding; in August 2026 approval was still being pursued. It is not approved anywhere.

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From brain drug to obesity candidate

Filled dots: trials and research · Open dots: regulators and developers

1. 2004–2008Trial or researchParkinson's and Alzheimer's trials (NS-2330): no benefit, but weight loss
2. 2008Trial or researchTIPO-1 obesity trial published: 203 people, 24 weeks
3. 2013Trial or researchExpression of concern about TIPO-1's side-effect recording
4. Dec 2018Trial or researchMexican phase 3 (372 people) top-line results
5. End 2019Regulator or developerMedix applies for approval in Mexico
6. 2021Regulator or developerFDA orphan designations for Tesomet (tesofensine + metoprolol), not approvals
7. Feb 2023Regulator or developerCOFEPRIS committee: favorable, non-binding opinion
8. Nov 2024Regulator or developerMexico withholds approval
9. 2025Regulator or developerNamed on WADA's list as a stimulant; Medix plans resubmission (Feb)
10. Dec 2025Regulator or developerFDA warning letter: ineligible for US pharmacy compounding
11. Aug 2026Regulator or developerApproval still being pursued in Mexico; not approved anywhere

Events spaced for reading, not to scale. Tesomet combines tesofensine with the heart drug metoprolol.

Tesofensine has reached phase 3, but no regulator has approved it; a favorable committee opinion is not an approval.

Typical Tesofensine Protocols

The most common protocol in the reviewed sources is 0.5 mg (500 mcg) taken by mouth once a day, in the morning. It is the dose the developer expects to use, the higher dose in the Mexican phase 3 trial and the usual daily amount on dosing websites, which typically start at 0.25 mg first. [18], [19], [20], [21], [22], [23]

Titration Changing the dose in steps

TIPO-1 and the Mexican phase 3 trial gave one fixed dose from the first day, and the developer says its tablet will not require titration. The TIPO-4 extension allowed a rise from 0.5 mg to 1.0 mg. Dosing websites instead start at 0.25 mg and move to 0.5 mg after anything from 4 days to 6 weeks; one says to step up only if resting heart rate stays within 10 beats a minute of its usual level. Short research studies did the opposite, giving a loading dose of 1–2 mg for 3–5 days so levels would rise faster. [1], [19], [18], [17], [20], [24], [25], [26]

Breaks and cycles

The trials gave tesofensine continuously for 24 weeks, and one extension ran to 48 weeks; none tested breaks. Websites describe 8–12 or 12–16 weeks of use followed by an equal time off, or 8 weeks on and 4 weeks off. No study has shown that breaks are needed or that they help. [1], [7], [27], [20], [21]

Read the units: each dose of tesofensine is measured in milligrams and micrograms; 0.25 mg is 250 mcg and 0.5 mg is 500 mcg. Online products are commonly labelled 250 or 500 mcg, but their strength has not been checked the way an approved medicine's is; the trials used study tablets. The daily total is everything taken in one day added together. Labels and posts sometimes write "mg" when they mean "mcg": 500 mg would be 1,000 times the trial dose. The tested form is a swallowed tablet, so no vial, mixing or syringe is involved. [28], [20], [29], [30]

Each row is a complete trial schedule. Low, mid and high were separate groups of people, not steps to move through. These are research doses from a trial of tesofensine alone, not an approved label; the cited references give the full details. [1], [31]

Before using any of these numbers, know the specific risks:

• Heart rate and blood pressure. Heart rate rose in the trials, and more at higher doses. People with heart disease, uncontrolled high blood pressure or abnormal heart tracings were kept out of the Mexican phase 3 trial. [26], [10], [1], [19]
• Antidepressants and other serotonin drugs. Trials banned antidepressants (SSRIs, SNRIs, MAO inhibitors and bupropion), anxiety medicines, lithium, opioids and appetite suppressants. Combining serotonin drugs can cause serotonin syndrome, and methylene blue's label warns against exactly this kind of combination. [7], [32]
• Mood and mental health. Small trials recorded serious psychiatric events, and the Mexican obesity trial excluded people with psychiatric illness. It has not been tested as a treatment for depression, attention-deficit/hyperactivity disorder (ADHD) or low motivation. [26], [33], [19]
• It builds up. With a half-life of about 9 to 10 days, each dose adds to the last for about six weeks, so a dose that feels mild in week one can feel stronger by week three, and sleep problems can outlast the last tablet. [7], [34], [35]
• Not studied in pregnancy or while breastfeeding, which were exclusions in the phase 3 trial, and in under-18s only in a tiny trial of Tesomet. [19], [33]
• Products are unverified. Tesofensine sold online is not an approved product, and how often labels get the strength or units wrong is unknown. [29], [36], [30]

What do dosing websites and community groups describe?

Dosing websites build on the trial doses but add a starting step, morning timing and planned breaks. The table below keeps one website's three complete schedules together; they are practice descriptions, not tested regimens. [20]

In community education groups, the amount members most often describe is lower still: about 125–250 mcg a day, often a quarter or half of a 500 mcg tablet, taken on waking with nothing after early afternoon. Many take it only on weekdays, every other day or a few times a week, and most take it alongside a GLP-1 drug. Public forum accounts show the same pattern. [37], [38], [39], [40]

Where protocols differ: starting doses, 1.0 mg, every-other-day use and breaks ↓

What is tesofensine commonly used for?

People look into tesofensine mainly to lose weight, usually by quieting hunger and cravings, and often on top of a GLP-1 drug such as semaglutide or tirzepatide. A second group takes it for energy, focus or mood, which no trial has tested. [45], [46], [47]

The trials show that tesofensine alone lowers body weight more than placebo when combined with a diet. They do not show how it performs alongside GLP-1 drugs, at the lower or intermittent doses many people use, or over more than a year.

Weight loss on its own

This is the best-studied use. In TIPO-1, 203 Danish adults with obesity followed a reduced-calorie diet and took tesofensine or a placebo for 24 weeks. Average weight loss was 6.5% on 0.25 mg, 11.2% on 0.5 mg and 12.6% on 1.0 mg, compared with 2.0% on diet and placebo, or 4.5, 9.2 and 10.6 percentage points more than placebo. In kilograms, that was 6.7, 11.3 and 12.8 kg versus 2.2 kg. Of the 203 people, 161 (79%) finished the trial. [1], [17]

A larger phase 3 trial in Mexico tested the two lower doses in 372 adults, most of them women, who all followed the same diet and exercise program. After 24 weeks, average weight loss was 5.3 kg on 0.25 mg and 8.6 kg on 0.5 mg, compared with 1.9 kg on placebo. The developer reports that people on 0.5 mg lost about 10% of their weight, and that more than half of them lost over 10%. These results were posted on a trial registry and in company reports; no peer-reviewed paper has been published. [19], [2], [48]

Two bar charts of average weight lost after 24 weeks. In the TIPO-1 trial, as a percentage of body weight: 2.0% on placebo, 6.5% on 0.25 mg, 11.2% on 0.5 mg and 12.6% on 1.0 mg. In the phase 3 trial in Mexico, in kilograms: 1.9 kg on placebo, 5.3 kg on 0.25 mg and 8.6 kg on 0.5 mg. All groups followed a diet.

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Average weight change after 24 weeks

Diet plus tesofensine or placebo, 24 weeks

TIPO-1 (Denmark, 2008)

% of body weight lost · 203 people

Placebo

2.0%

0.25 mg a day

6.5%

0.5 mg a day

11.2%

1.0 mg a day

12.6%

Phase 3 (Mexico, results 2018)

kg lost · 372 people

Placebo

1.9 kg

0.25 mg a day

5.3 kg

0.5 mg a day

8.6 kg

All groups followed a diet. TIPO-1 carries a 2013 expression of concern about side-effect recording. Mexican results: registry summary, not peer-reviewed.

In both trials, tesofensine plus diet beat placebo plus diet, and higher doses lost more.

Two caveats travel with these numbers. The 2008 TIPO-1 paper carries an expression of concern about how its side effects were recorded, although its weight results were not withdrawn. And both trials combined the drug with a diet; in older neurology trials with no diet, average weight fell by only 0.5% to 2.8% over 14 weeks, depending on dose. Why the concern matters. [31], [10]

Hunger, cravings and "food noise"

Many people describe tesofensine in terms of appetite: feeling full sooner, smaller portions and fewer intrusive thoughts about food, often called food noise. In trials, people on tesofensine rated their fullness higher and their hunger lower than people on placebo. [49], [50], [51]

That effect faded. In TIPO-1, the appetite effect was clear at week 12 and smaller by week 24 as weight fell; after a drug-free gap it returned to baseline, and it rose again when tesofensine was restarted. The researchers could not tell whether the drug itself was wearing off or the body was pushing back against weight loss. Some people online describe the same early suppression that later faded. [49], [40]

Adding it to semaglutide, tirzepatide or retatrutide

In the reviewed discussions, many people take tesofensine with a weekly GLP-1-type injection: to cover hunger that returns late in the week, to break a weight-loss plateau, or as a "bridge" while pausing or switching the injection. No trial has tested tesofensine with any of these drugs. In one of the developer's trials, injectable diabetes medicines were on the list of banned drugs. [46], [52], [53], [7]

Community education groups disagree sharply about this use; their positions are summarized below. See the Doserly guides to semaglutide, tirzepatide and retatrutide.

Energy, focus and mood

Many online accounts value tesofensine more for energy, motivation or focus than for appetite, and some use it to self-treat low mood, ADHD symptoms or the flat mood some people notice on GLP-1 drugs. None of these uses has been tested. Tesofensine did not improve Parkinson's disease or Alzheimer's disease in trials, and its effects on mood run in both directions: small trials recorded serious depression and hypomania. Mood risks are covered below. [54], [47], [55], [8], [9], [26]

Rare obesity conditions (Tesomet)

Tesomet, the combination with metoprolol, has been tested in small trials for hypothalamic obesity (weight gain after damage to the hypothalamus, often from brain-tumor surgery) and Prader-Willi syndrome (a genetic condition with constant hunger). FDA has given it orphan designation for both, which supports development but is not an approval. These results belong to the combination, not to tesofensine alone. [56], [33], [15], [16]

Other uses you may come across

Two popular claims go beyond the evidence. "Boosts metabolism": in a two-week study, tesofensine did not significantly change total daily energy use, although night-time energy use rose by 4.6%; appetite is the main effect. "Preserves muscle": the body-scan results we could access, from the Tesomet trial in hypothalamic obesity, showed a significant loss of lean mass (2.76 kg versus a 0.36 kg gain on placebo). [50], [57]

See the full trial results or how it works.

Where do tesofensine protocols differ?

The trial doses are simple: one fixed amount, once a day, for 24 weeks. The disagreements start when people use it differently, with a starting step, days off, breaks or other drugs. Here is what those differences mean.

Start at 0.25 mg, or take the full dose from day one?

TIPO-1 and the Mexican phase 3 trial gave the full dose from day one and did not step it up, and the developer expects no titration for its tablet. Only the TIPO-4 extension allowed a rise, from 0.5 mg to 1.0 mg. Dosing websites almost all start at 0.25 mg, then move to 0.5 mg after periods ranging from 4 days to 6 weeks. [1], [19], [18], [17], [24], [20], [25]

The half-life explains why a starting step changes less than it seems. Levels keep rising for weeks whatever the dose, so the first week at 0.25 mg mostly delays when the full effect arrives. In short research studies, investigators did the opposite of titration: they gave 1–2 mg a day for the first 3–5 days to reach steady levels sooner. [7], [26]

Is 1.0 mg better than 0.5 mg?

Only slightly, for weight. In TIPO-1, 1.0 mg led to 12.6% average weight loss versus 11.2% on 0.5 mg, about 1.4 percentage points more. Side effects rose with dose: in pooled neurology trials, heart rate rose by 6.0 beats a minute on 0.5 mg and 6.8 on 1.0 mg, and two reviews report a rise in blood pressure at 1.0 mg that was not seen at the lower doses. [1], [10], [58], [59]

The developer chose 0.5 mg as its expected dose and dropped 1.0 mg from the phase 3 trial. Its summary also notes that hallucinations in older patients occurred mostly at doses above 0.75 mg a day. Five dosing websites list 1.0 mg as an upper amount. TIPO-1 tested 1.0 mg daily for 24 weeks; the later Mexican phase 3 trial tested only 0.25 and 0.5 mg. [18], [19], [7], [20], [28], [1]

Every day, every other day, or a few times a week?

Every trial used daily dosing, except one small trial in teenagers with Prader-Willi syndrome that gave 0.25 mg every second day to average 0.125 mg a day. Online, weekdays-only, every-other-day and three-times-a-week schedules are common, often to limit insomnia or to stretch a supply. [60], [38], [39], [37]

Because tesofensine lasts so long, days off do not create drug-free days. By our calculation from the measured half-life, about 86% of the drug in the body is still there 48 hours after a dose, so 500 mcg every other day ends up at roughly the same average level as 250 mcg every day. In the figure's comparison, the every-other-day amount is doubled, so both schedules deliver the same amount over time; halving the weekly total instead would halve the level, but neither schedule creates drug-free days. [7], [34]

Illustrative line chart of tesofensine levels over 120 days, as a percentage of the steady level reached with daily dosing. With daily doses the level rises to about 41% after 1 week, 65% after 2 weeks and 96% after 6 weeks. Every-other-day dosing at twice the amount zig-zags around the same curve, between about 93% and 108% at the plateau. After the last dose on day 70, half is gone after about 9 days and about 12% is left after 4 weeks.

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Why tesofensine builds up for weeks

Illustrative calculation from the measured half-life, not measured blood levels

Daily doses

About 41% of the steady level after 1 week, 65% after 2 weeks and 96% after 6 weeks.

Twice the dose every other day

Reaches a similar average; at the plateau it swings between about 93% and 108%, versus about 96% to 104% with daily doses.

After the last dose

About half is gone after 9 days, and about 12% is left after 4 weeks.

One-compartment calculation with a half-life of 220 hours; absorption ignored. The daily line shows the average level; each daily dose adds a ripple of about ±4%.

Levels climb for about six weeks, and twice the dose every other day ends at about the same level: skipped days are not drug-free days.

Morning, or later in the day?

Trial participants took their tablet each morning with or right after a meal. Dosing websites describe taking it first thing, some specifying before 9 am or on an empty stomach; no study has compared times of day. Online accounts warn that afternoon or evening doses wreck sleep. With a long half-life, timing shifts when the peak falls rather than preventing overnight exposure, which may be why some people report insomnia even with early doses. [61], [27], [20], [62], [63], [64]

How long, and are breaks needed?

The obesity trials ran for 24 weeks, and the open-label extension for 48. Websites describe 8–12 weeks on with an equal break, 12–16 weeks on with an equal break, 8 weeks on and 4 off, or 12–24 weeks with no break stated. Community education groups report even wider patterns, from single trial doses to courses of several months each winter. [1], [7], [27], [20], [21], [65]

No study has compared cycling with continuous use. The reason websites give for breaks, avoiding a lasting change in dopamine signaling, has not been tested in people. [27]

Where do the sources disagree most?

• Starting step: trials used a fixed dose; websites add a 0.25 mg start; research studies used 1–2 mg loading doses. [1], [20], [26]
• Upper amount: 0.5 mg on most websites and in phase 3; 1.0 mg on five websites; one online account calls 1,000 mcg a day "fine" after reading dosing pages. [18], [41], [28], [66]
• Trial numbers: several pages report TIPO-1's weight losses as 6.7%, 11.3% and 12.8%. Those figures are kilograms in the developer's results announcement; the percentages were 6.5%, 11.2% and 12.6% in total, or 4.5, 9.2 and 10.6 points more than placebo. Others attach the 1.0 mg result to 0.5 mg or call the trial 14 weeks long. [27], [20], [21], [67], [42], [17], [1]
• Approval and supply: some pages say Mexico approved tesofensine in 2023 or that US compounding pharmacies can supply it. Neither is correct. [68], [44], [3], [36]

Is tesofensine ever injected, or made into a liquid?

The tested form is a tablet. One dosing website presents it as a subcutaneous (into the fatty layer under the skin) injection with vial arithmetic, a template borrowed from injectable peptides, and one online account describes weekly injections followed by no benefit and lasting ear ringing. No human study has tested injected tesofensine; the only non-oral human study was a single infusion into a vein. [42], [63], [69]

People who buy bulk powder sometimes make their own liquid. In one public forum thread, a proposed recipe would have made each dose 10 times stronger than intended before another member caught the error. How the forms compare. [70]

What about Tesomet, "brain blends" and other stacks?

Combinations are sold and discussed by their product names. Read the amount of tesofensine in each, not the total weight:

Only Tesomet has been tested in people, and those trials say nothing about the other combinations. Combining tesofensine with methylene blue deserves particular caution because of serotonin syndrome; see interactions. Read the Doserly guides to Dihexa, the Dihexa, methylene blue and tesofensine blend, 5-Amino-1MQ and BPC-157.

What happens when you stop tesofensine?

The drug leaves slowly, and appetite and weight tend to return. TIPO-1 followed people for eight weeks after the last dose, and the developer later reported that they had regained some weight during the two-month gap before the TIPO-4 extension; no detailed regain figures or longer follow-up have been published, and no study has looked specifically at withdrawal effects. [17], [76], [49], [60]

• Appetite comes back. In the TIPO-1 follow-up, fullness scores returned to where they started after a drug-free gap of about 12 weeks, even though people were still about 7 kg lighter, and rose again when tesofensine was restarted. In rats, food intake and weight gain crept back up after the drug was stopped. [49], [77]
• It lingers for weeks. With a half-life of about 9 days, and about 16 days for its main breakdown product, it takes roughly six to seven weeks for most of the drug to clear, by our calculation. After a single 483 mcg dose, anti-doping researchers could detect it or its breakdown products in urine for up to about 500 hours (three weeks). [7], [34], [29]
• Trials stopped without tapering. Trial protocols stopped the drug at once when someone withdrew; no study has compared tapering with stopping all at once. [60]
• What people report. Online accounts describe sleep problems lasting about a week after stopping, weight returning after stopping for cost, low mood, anxiety and poor focus returning after a slow taper, and lethargy with a mild headache after two missed days that one person compared with stopping an antidepressant. Others report no problems at all after months of use. Community education groups show the same split between members who taper over several weeks and those who stop at once. [35], [78], [79], [53], [80]

The long half-life cuts both ways: it softens an abrupt stop, but it also means side effects such as insomnia or a raised heart rate can take a week or more to settle.

How is tesofensine taken, and how long does it stay in the body?

Tesofensine is taken orally, as a tablet or capsule swallowed once a day. Unlike most compounds sold alongside it, it does not need to be injected: more than 90% of a swallowed dose reaches the bloodstream (its bioavailability), and taking it with food makes little difference. In trials, people took it each morning with or right after a meal and were told not to crush or chew the tablets. [7], [61]

Its most important property, in the language of pharmacokinetics (how the body absorbs, handles and removes a drug), is how long it lasts. The half-life, the time for blood levels to fall by half, is about 220 to 234 hours, or 9 to 10 days. The body turns it mainly into one breakdown product (metabolite), called NS2360 or M1, which lasts even longer, about 374 hours (about 16 days). That metabolite is much weaker; the developer estimates it provides about 6% of the drug's activity. [7], [34], [81]

Because so little leaves the body each day (about 7%, by our calculation), levels climb with every daily dose and reach a stable plateau, called steady state, only after about five half-lives: roughly six to seven weeks. That is why a side effect such as insomnia can appear in the second or third week rather than the first, and why it can outlast the last tablet. [7], [34], [54]

A few groups keep more of the drug in their blood:

• Kidney problems. Exposure was about 30% higher in people with moderate or severe kidney impairment. In a modelling study, women with reduced kidney function had 62% higher exposure than men with normal kidneys. [7], [34]
• Some other medicines. Itraconazole, an antifungal that blocks the liver enzyme CYP3A4, raised tesofensine exposure by 63% in a modelling analysis, although a simpler analysis of the same study found a smaller rise. See interactions. [82]

Does tesofensine come as an injection, a liquid or a strip?

Not as a tested product. Online it appears as capsules, tablets, oral liquids and bulk powder, one dosing website treats it as an injection, and community education groups also describe dissolving strips blended with other compounds. The obesity and neurology trials used study tablets, and a 2026 anti-doping study gave six volunteers one capsule sold as a supplement (483 mcg). No human study has tested oral liquids, strips or injections; the only non-oral route studied was a single slow intravenous infusion (into a vein) in healthy volunteers. Given that swallowed tesofensine is already almost fully absorbed, a different route has no demonstrated advantage. [7], [29], [69], [42], [28], [83], [70], [63]

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

There is no approved product label and no published stability study, so the only primary storage instruction comes from the developer's trials: keep the tablets at room temperature, 15–25 °C, and protected from light. [61]

• Tablets and capsules. The trial condition above applies to the developer's tablets; no shelf life after opening has been published, and we found no stability testing of products sold online. [61]
• Liquids and strips. No stability data exist for home-made or sold liquids, drops or strips. How long they keep, and whether the amount per dose stays accurate, is not established. [70]
• Powder. Bulk powder has no published storage data either, and measuring a dose of a few hundred micrograms from it requires accurate equipment. [70]

This guide does not cover preparing or measuring doses by hand. The Academy note below points to practical basics.

What do we actually know about tesofensine in people?

More than most compounds sold beside it. Tesofensine has been through randomized, placebo-controlled trials in people with obesity, Parkinson's disease and Alzheimer's disease, and its developer counts 1,921 people exposed across 34 clinical trials. The limits are in the details: the main obesity paper carries an expression of concern, the phase 3 trial has no peer-reviewed paper, and no trial lasted longer than 48 weeks. [2], [1], [31], [19]

What did the obesity trials find?

The two main trials point the same way: more weight loss than diet alone, larger at 0.5 mg than at 0.25 mg. Their results cannot be pooled directly, because one reported percentages and the other kilograms, and the populations differed.

Why does the 2008 trial carry an expression of concern?

In 2013, The Lancet published an expression of concern about TIPO-1, a formal notice that questions have been raised about a paper. It followed an inspection by the Danish Health and Medicines Authority in 2011 of two of the five trial sites. The inspectors found that side effects had been recorded incompletely: headache, migraine, stress and depression were not logged as side effects when people already had them before the trial started. They also found that consent had been handled by non-medical staff at one site and questioned how well the treatment was kept hidden from participants and staff. [31], [85], [56]

The authors replied that these events had been under-reported at all centres. The weight results were not retracted, but the side-effect profile published in 2008 is known to be incomplete, particularly for mood-related effects. That is one reason this guide leans on the later trials for safety. [86], [56]

What did the Parkinson's and Alzheimer's trials show?

Tesofensine was first tested as a brain drug. In 261 people with early Parkinson's disease, 14 weeks of 0.25–1.0 mg did not improve symptoms more than placebo. In advanced Parkinson's, stomach and psychiatric side effects were more common than on placebo, especially at higher doses. A 430-person Alzheimer's trial was also negative. [8], [87], [9]

Those trials still matter, because they supplied the first safety and weight data. Pooled across four of them, 740 people took tesofensine and 228 took placebo for 14 weeks with no diet: weight changed by +0.5% on placebo and by −0.5% to −2.8% on tesofensine, and heart rate rose by 2.1 to 6.8 beats a minute depending on dose, with no effect on blood pressure. [10]

What did the Tesomet trials add?

Tesomet adds metoprolol to cancel out tesofensine's rise in heart rate. In a 23-day study built to find the right amount, the metoprolol dose needed to fully cancel it rose steeply with the tesofensine dose: about 10 mg at 0.25 mg, 61 mg at 0.5 mg and 148 mg at 0.75 mg. [26], [7]

• Hypothalamic obesity: 21 adults, 0.5 mg tesofensine plus 50 mg metoprolol, 24 weeks. Weight fell 6.3% more than on placebo, heart rate and blood pressure did not differ between groups, and lean mass fell by 2.76 kg. Sleep problems affected 50% versus 13% on placebo. The developer funded the trial, and several authors worked for it. [56], [57]
• Type 2 diabetes: 60 adults, 0.5 mg plus 100 mg metoprolol, 90 days. Average 24-hour heart rate was 67 versus 70 beats a minute on placebo, weight fell 3.5 kg more, and blood sugar control (HbA1c) did not change. [71]
• Prader-Willi syndrome: only 9 adults were randomized; 3 of the 6 on Tesomet had serious psychiatric events, and 4 of the 6 did not finish. [33]

These results belong to the combination. They show that metoprolol can blunt the heart-rate rise; they do not show that tesofensine alone is safe for the heart.

What would a useful result look like in everyday life?

An average of about 10% weight loss in a trial describes a group, not a person. Within the phase 3 trial, the developer reports that more than half of people on 0.5 mg lost over 10%, which also means that many lost less. Tesofensine also changes several things at once: hunger, sleep, heart rate and mood all shifted in the trials, so the useful question is how each of them moved, not only the number on the scale. [2], [49], [26]

What don't the trials tell us?

• Long-term safety: no trial lasted longer than 48 weeks, and we found no study that measured heart attacks, strokes or deaths. [7], [2]
• Use with GLP-1 drugs: untested, although it is a common way people use it online.
• Intermittent or low doses: no obesity trial tested weekday-only use or doses below 0.25 mg.
• Weight after stopping: TIPO-1 had eight weeks of follow-up and the developer reported some regain before the extension began; no detailed or longer-term data have been published. [17], [76]
• Who was studied: the Mexican obesity trial excluded people with heart disease, psychiatric illness and other conditions, so their safety results may not apply to everyone who uses it. [19]

How does tesofensine work?

Laboratory studies show that tesofensine blocks the transporters that pull three brain chemicals back into nerve cells, and brain scans in people have measured it blocking one of them, the dopamine transporter. How that turns into eating less is less certain, and most of the detail comes from animal studies.

Which brain chemicals does it affect?

Nerve cells release dopamine, noradrenaline and serotonin into the tiny gap between cells, then recycle them through pumps called transporters. Tesofensine blocks all three pumps, so it is called a triple reuptake inhibitor. Antidepressants such as SSRIs block only the serotonin pump. A 2009 review described tesofensine's profile as similar to that of sibutramine, an older weight-loss drug. [1], [50], [88]

In people, brain scans (PET) measured how much of the dopamine pump it occupied. After 8–12 days of 0.125–1 mg a day, occupancy ranged from 18% to 77% depending on the dose, with a ceiling of about 80%, and about half of the maximum effect was reached at 0.25 mg. That helps explain why 0.25 mg already has noticeable effects in some people. [6]

In a 2025 laboratory study, researchers imaged the dopamine pump with tesofensine bound to it at near-atomic detail and found that it locks the pump in an outward-facing position. That is a cell study of the protein itself. [89]

Why does it curb appetite?

In people, tesofensine raised feelings of fullness and lowered hunger and the amount people expected to eat. [49], [50]

The brain circuits behind that come from animal studies. In obese rats, its appetite effect was almost completely blocked by a drug that blocks one type of noradrenaline receptor (alpha-1) and partly blocked by one that blocks a dopamine receptor (D1). It restored low dopamine levels in a reward area of the brain in obese rats. In mice, it quieted a group of feeding-promoting nerve cells in the lateral hypothalamus, an appetite center; that study used drug supplied by the Mexican licensee. [90], [91], [92]

Does it make you burn more calories?

Only slightly, if at all. In a two-week study in a sealed metabolism room, tesofensine did not significantly change total daily energy use. Energy use during the night was 4.6% higher and fat burning rose by 18 g a day, but the researchers concluded that appetite was the main driver of weight loss. Claims of a large "metabolism boost" overstate this. [50]

Why does it raise heart rate, and what does metoprolol do?

Noradrenaline is also the body's "fight or flight" signal, so blocking its recycling can speed the heart. In rats, tesofensine raised both heart rate and blood pressure, and metoprolol, a beta-blocker, prevented those rises without weakening the appetite effect. In people, the heart-rate rise grew with dose, and the metoprolol needed to cancel it grew too. That is the idea behind Tesomet. [93], [26]

What about the long-lasting breakdown product?

The liver converts tesofensine mainly into one metabolite, NS2360 (also called M1), with help from the enzyme CYP3A4. It stays in the blood longer than tesofensine itself but is 4–5 times weaker at the dopamine pump in mice, and the developer estimates it provides about 6% of the drug's activity. [7], [82], [81]

What are the risks and unanswered questions?

Is tesofensine safe?

Its safety has not been established well enough for any regulator to approve it. Trials in more than a thousand people give a clear picture of its common effects, but they also show a steady rise in heart rate, frequent sleep problems and occasional serious psychiatric events, and none lasted longer than 48 weeks. [2], [10], [26], [7]

Two gaps make the picture less reassuring than the numbers suggest. The main obesity paper's side-effect records are known to be incomplete, and the phase 3 trial's side-effect tables have not been published. The registry summary says 65% of participants had at least one side effect (adverse event), with similar proportions across the groups, and that the two severe events (a tendon rupture and a gallbladder inflammation) were judged unlikely to be related. [31], [19]

What side effects did the trials find?

Heart rate rose in every trial of tesofensine alone that reported it, and more at higher doses:

In the 23-day study, the highest heart rate recorded during each day averaged about 126 to 135 beats a minute by the last day, and 16 of 37 volunteers reported palpitations (a pounding or racing heartbeat). [26]

Blood pressure did not rise significantly on 0.25 or 0.5 mg in TIPO-1 or in the phase 3 trial, but reviews of TIPO-1 report a rise at 1.0 mg; those 1.0 mg figures come from the full paper, which we could not access. We found no study that measured heart attacks or strokes. [1], [2], [58], [59]

Other common effects in the trials were dry mouth, trouble sleeping, nausea, constipation, hard stools, diarrhea, headache and dizziness. The developer's summary lists headache, insomnia, dizziness, sleepiness, loss of appetite, lack of energy, dry mouth, poor attention, cold-like symptoms, diarrhea and constipation as affecting more than 1 in 10 people, and sweating, palpitations and blurred vision as less common. Insomnia was the most common side effect of this class of drug in a review of obesity medicines acting on the brain. [1], [7], [71], [94]

Can tesofensine affect mood or mental health?

Yes, in both directions. Mood effects are the least well measured part of its record, because they were under-recorded in TIPO-1. [31], [56]

• In the 23-day heart-rate study, 2 of 37 otherwise healthy volunteers had serious psychiatric events: one on 0.5 mg had hypomania (an abnormally elevated, driven mood) and depression, and one on 0.75 mg had depression and an impulse-control disorder. Eleven reported euphoric mood. Completion fell with dose: 9 of 9, 12 of 16 and 5 of 12. [26]
• In the Prader-Willi trial of Tesomet, 3 of 6 adults had serious events: anger, hallucination and abnormal behaviour. In the hypothalamic-obesity trial, one person's existing anxiety worsened enough to stop treatment. [33], [56]
• The developer expects dopamine-related effects such as insomnia, agitation, hallucinations, psychosis, paranoid thinking and depression, and reports that hallucinations in older patients occurred mostly above 0.75 mg a day. [7]

The developer's later trials screened participants for suicidal thoughts with a standard questionnaire and excluded anyone with recent suicidal behaviour, and the Mexican trial excluded people with psychiatric illness. A review also noted that drugs of this class can lift mood and anxiety in some people. That is exactly the group that has not been tested: people using it to self-treat depression, ADHD or anxiety. [95], [19], [94]

Is tesofensine addictive?

A single-dose study in 52 people who used stimulants recreationally found that tesofensine felt no different from placebo on the main "drug liking" measures, and less than amphetamine; its abuse potential was judged no greater than that of bupropion or atomoxetine. That was one dose. It does not test dependence or what happens after months of daily use. [96]

Some online accounts describe feeling unwell after missed doses or a return of low mood after stopping. See what happens when you stop. [53], [79]

What about ringing in the ears (tinnitus)?

About ten public threads describe tinnitus starting on tesofensine, and several say it lasted weeks to months after stopping. We found no mention of tinnitus in the trial records reviewed, and these accounts cannot show that tesofensine caused it; some posters also had colds, other drugs or earlier tinnitus. It is an unconfirmed report worth knowing about, not an established side effect. [35], [52], [63], [97], [98], [99], [26], [71]

Could product quality change the risk?

Yes. Products sold online have not been through any medicine approval. In the one published test of a product bought online, anti-doping chemists found 483 mcg in a capsule labelled 500 mcg, so trial-strength products are being sold as "dietary supplements." Other accounts describe a seller shipping the wrong strength or mixing up mg and mcg, but how often this happens is unknown. Claims that most tesofensine sold online is fake are unsupported either way. [29], [100], [30], [101]

Is tesofensine legal? Is it FDA-approved?

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

United States. Tesofensine is not FDA-approved; FDA's drug databases list no application or label for it. [102]

• 2021. FDA granted orphan designation to the tesofensine and metoprolol combination (Tesomet) for hypothalamic obesity and Prader-Willi syndrome. That supports development of a rare-disease medicine; it is not an approval. [15], [16]
• December 2025. An FDA warning letter to a supplier of drug ingredients listed tesofensine among ingredients that are not eligible for use by US pharmacies making compounded medicines. Websites and telehealth services offering "compounded tesofensine" conflict with that. [36], [44]
• May 2026. Tesofensine does not appear on any of FDA's lists of ingredients nominated for pharmacy compounding, so no review that could open that route is under way. [103]
• 2026. The developer says FDA has agreed a development route for Tesomet; no application has been approved. [2]

Mexico. Not approved.

• 2018–2019. The phase 3 trial reported positive results, and Medix applied for approval at the end of 2019. [48], [12]
• February 2023. A technical committee of COFEPRIS, Mexico's regulator, gave a favorable opinion, which the developer said "does not represent a market authorization or rejection." [12]
• November 2024. Medix had not received approval, and the developer described COFEPRIS's decision to withhold it. [3], [13]
• 2025–2026. Medix planned to resubmit in February 2025, and in August 2026 it was still pursuing approval. Web pages claiming that Mexico approved tesofensine, or products called "Tesomet" or "Nupenta," in 2023 are wrong. [104], [2], [68]

Canada. No product containing tesofensine is authorized; Health Canada's drug database returns none. Health Canada warns that labels such as "For research use only, not for human consumption" do not make unauthorized products legal. [105], [106]

Australia. Not approved. No tesofensine product is on the Australian Register of Therapeutic Goods, the register of approved medicines. Australia has limited legal routes for some unapproved medicines, such as special-access schemes and clinical trials; we found no record of tesofensine being supplied through them. It is also not named in Australia's Poisons Standard (the June 2026 edition), the national list that sets which medicines need a prescription. Not being named in that list does not make a product approved or legal to sell. [107], [108]

European Union and United Kingdom. Not approved. The European Medicines Agency's records of medicines reviewed for the whole EU contain no application or approval for tesofensine, and the UK regulator's medicines database has no product containing it. National registers of individual EU countries were not searched. [109], [110]

A "research use only" label does not make a product legal to sell for people to take, or safe to use.

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

Yes, in competition. The World Anti-Doping Agency's 2026 Prohibited List names tesofensine as a stimulant (category S6.B, specified stimulants), banned in competition only; it has been named since the 2025 list. [111], [112], [29]

Anti-doping labs can detect it. After a single 483 mcg dose, researchers found tesofensine or its breakdown products in urine for up to about 500 hours (three weeks). We found no study of whether it triggers standard workplace drug screens for amphetamines or cocaine, a question that comes up in online discussions. [29], [113]

Who should be especially cautious?

These groups either have specific risks or were kept out of the trials. Having no data is a reason for caution, not proof of harm.

• Heart and blood-pressure conditions. Heart rate rises with dose, and people with heart disease, uncontrolled high blood pressure or abnormal heart tracings were excluded from the phase 3 trial. [26], [19]
• Depression, bipolar disorder, anxiety or psychosis. Serious psychiatric events occurred in small trials, and psychiatric illness was an exclusion. Community education groups also caution people with a history of addiction or binge eating. [26], [33], [19]
• People taking antidepressants or other serotonin drugs. See interactions below.
• Kidney problems. Exposure rises with reduced kidney function. [7], [34]
• Pregnancy and breastfeeding. Excluded from the phase 3 trial; no human data. [19]
• Under 18. The only young people studied were a few teenagers with Prader-Willi syndrome taking Tesomet. This guide is written for adults. [33]
• Older adults. Psychiatric side effects were more common in older patients in the neurology trials. [7]
• Competitive athletes. Banned in competition. [111]

Does tesofensine interact with other medicines?

Very few interactions have been tested, and the most important risks are predicted rather than measured. What is known:

• Drugs the trials banned. The developer's trial protocols did not allow SSRIs, SNRIs, MAO inhibitors, other antidepressants, bupropion and other dopamine reuptake inhibitors, anti-anxiety drugs, benzodiazepines, lithium, opioids, anti-seizure drugs, Parkinson's medicines and other appetite suppressants. These are exclusion lists, not interaction studies, but they show which combinations the developer chose not to risk. [7]
• Serotonin syndrome. Tesofensine blocks serotonin recycling, so combining it with other drugs that raise serotonin could cause serotonin syndrome, a dangerous excess of serotonin. We found no reported case with tesofensine; the concern comes from how it works. The US label for intravenous methylene blue (ProvayBlue) carries a boxed warning that it can cause serious or fatal serotonin syndrome with serotonergic drugs and opioids, and says to avoid combining it with SSRIs, SNRIs, MAO inhibitors and opioids. Tramadol, linezolid, dextromethorphan and triptans raise the same theoretical concern. [1], [32]
• Drugs that block CYP3A4. Itraconazole raised tesofensine exposure by 63% in a modelling analysis; the developer states that its interaction studies found no clinically relevant effect. Because the drug lasts so long, even a modest rise builds up over weeks. [82], [7]
• Stimulants and caffeine. Not studied. Dosing websites warn that it amplifies caffeine and should not be combined with other stimulants, and community education groups describe overstimulation when it is taken with coffee. [27], [20]
• GLP-1 drugs. Not studied, although it is a common combination online. [7]

Bring a complete list of everything you take, including supplements and other compounds, to a pharmacist or doctor.

What should be monitored while using tesofensine?

There is no official monitoring plan, because no regulator has approved tesofensine or written a label for it. What exists is a record of what its trials measured and why. It can help you prepare questions for a clinician; it is not a personal testing plan. [102], [7]

What did the trials check?

• Heart rate and rhythm. The later trials used 24-hour or 48-hour heart monitors (Holter monitors) and electrocardiograms (ECGs, recordings of the heart's electrical activity); in the 23-day heart-rate study, the average 24-hour heart rate was the main result. Blood pressure was measured over 24 hours in the hypothalamic-obesity trial. [56], [26], [84]
• Mood and suicidal thoughts. The developer's later trials used a standard depression questionnaire (the PHQ-9), including its question on suicidal thoughts, with rules for stopping. [7], [95]
• Blood tests. Liver enzymes, blood counts, salts and creatinine (a kidney marker) at each visit; blood sugar and HbA1c in the diabetes trial. [56], [71]
• Body composition. Body scans measured fat and lean mass in the hypothalamic-obesity trial, which is how the lean-mass loss was found. [56], [57]
• Eyes. The 48-week extension listed eye examinations among its safety checks. [84]

Which signals matter, and why?

Because levels build for about six weeks, a change in heart rate, sleep or mood may show up weeks after starting or after a dose change, and can take a week or more to settle after stopping. The trial measurements show what researchers watched for; they are not thresholds that make use safe. Discuss any testing with a clinician. [7], [26], [49]

What do people in public communities report?

Public discussions of tesofensine mix strong appetite control, little or no effect, and side effects that made people stop, often in the same thread. Most accounts involve other drugs at the same time, especially GLP-1 injections, and the most useful ones return with an update weeks later. [45], [114], [78]

What do the positive reports look like?

A typical positive account describes appetite and cravings dropping within days. One person taking 0.25 mg each morning for two weeks described losing sugar and alcohol cravings and eating about 1,800 calories a day without effort; insomnia in the first three nights settled by the fourth or fifth. Another, adding 500 mcg to retatrutide for 10 weeks, reported losing 11 lb and said cravings were gone, with a slightly raised heart rate. [51], [46]

Neither account can separate tesofensine from what else was happening. The second person was also increasing their retatrutide dose, and the first had been on a very different diet the year before. That is the rule rather than the exception: in the public threads reviewed, most weight-loss stories involved a GLP-1-type drug. [46], [51]

What about energy, focus and mood?

Many people describe it as a clean energy or focus drug more than an appetite drug. One person with ADHD and low mood reported better focus, mood and motivation at 125–250 mcg every other day, but the energy boost faded after about two weeks and sleep worsened as doses accumulated, so they settled on occasional small doses. Another, using it for months for focus and mood, found anxiety and low mood returned within weeks of a slow taper and resolved when they restarted. They read that as a return to baseline rather than withdrawal. [37], [79]

These are self-treatment stories about conditions tesofensine has not been tested for, and they sit alongside serious mood events in trials.

How long did the effects last?

Early effects often faded. Several accounts describe strong appetite suppression in the first weeks that wore off, matching the trial finding that fullness scores rose early and declined by week 24. Others describe side effects that arrived late: sleep that was fine for the first days and then worsened as levels built up. [40], [49], [54], [115]

Does everyone notice a difference?

No. Some people describe no appetite effect at all, including at 500 mcg for 10 days or months of daily use, while others felt strongly stimulated at a quarter tablet. In one thread, one person felt nothing at 500 mcg and was "wired" at 750 mcg, while another had anxious chest tightness on a fraction of a 250 mcg capsule. [116], [99], [117], [75]

What unwanted effects come up?

• Sleep is the most common complaint by far: trouble falling asleep, waking at 2 or 3 am, or only a few hours a night, sometimes lasting about a week after stopping. [118], [64], [54], [119], [78]
• Heart rate and blood pressure: noticeable rises, one account of a 14-beat rise in resting heart rate while on many other drugs, and one of nearly blacking out on standing. [120], [121], [47]
• Mood: anxiety, a "crash" as effects wear off, and loss of enjoyment. [100], [122], [54]
• Other: dry mouth, constipation that returned each time the person restarted, diarrhea, rash, teeth grinding and, in about ten threads, ringing in the ears. [78], [123], [115], [30], [37], [35]

These are individual reports. They show what people noticed, not how often each problem happens or whether tesofensine caused it. The risks section covers what trials measured.

What do community education groups teach?

Community education groups are split. Some educators advise against tesofensine altogether, especially for people with a history of depression, anxiety, addiction or binge eating, anyone on antidepressants, and as a bridge during a GLP-1 break. Others, including some who sell or promote products, recommend it as a GLP-1 add-on at 0.25–0.5 mg each morning. Members most often report 125–250 mcg, and several describe combining it with methylene blue even though other educators warn against that pairing. Where their advice conflicts with the trial record, such as claims that tesofensine is approved in Mexico, boosts metabolism or preserves muscle, the trial record is covered in uses and legal status.

How can you judge a tesofensine story?

Useful questions to ask: What dose, how often, and for how many weeks? What else changed at the same time, especially a GLP-1 dose? How were sleep, heart rate and mood affected, not only weight? Did the effect last past the first month? What happened after stopping? Was the product's strength ever checked?

These selected discussions help identify questions and experiences worth knowing about. They are not a survey of all users, a response rate or a substitute for controlled trials.

How does tesofensine compare with semaglutide, orforglipron, cagrilintide and 5-Amino-1MQ?

These are the weight-loss drugs and compounds tesofensine is most often weighed against or combined with. No study has compared any of them directly with tesofensine, so the table compares what each one is and how much is known in people. Status was checked on September 24, 2026.

The biggest difference is how they work. Semaglutide, orforglipron and cagrilintide copy or mimic fullness hormones from the gut and pancreas; tesofensine acts on brain chemicals, and its trials recorded rises in heart rate, sleep problems and mood effects alongside some stomach and bowel side effects. Separate trials cannot show which drug has fewer side effects. The weight results come from separate trials of different lengths in different people, so the table cannot rank them, and tesofensine's two main trials lasted 24 weeks compared with 68 to 72 weeks for the others. Only semaglutide and orforglipron are approved. [1], [124], [125], [126], [129], [26]

Common questions about tesofensine

Is tesofensine a peptide? Is it a stimulant?

It is not a peptide. Tesofensine is a small lab-made molecule from the tropane family, sold alongside peptides only because the same websites carry weight-loss compounds. It is also not a classic amphetamine-type stimulant, but it blocks the recycling of dopamine and noradrenaline, can raise heart rate and disturb sleep, and anti-doping rules classify it as a stimulant. It is taken as a tablet, so injection and mixing instructions written for peptides do not apply. [4], [5], [111], [26] See what tesofensine is.

How long does tesofensine take to work?

Appetite changes are often described within days, but the drug keeps building up for about six weeks. In trials, fullness scores were clearly higher by week 12, and weight was measured at 24 weeks. Some people notice little or no effect, early suppression sometimes fades, and side effects such as insomnia can appear late as levels rise. [49], [1], [7], [51], [40] See what people reported over time.

Is tesofensine approved in Mexico?

No. Mexico's regulator gave a favorable committee opinion in 2023 but did not approve the application in November 2024. The Mexican partner planned to resubmit in 2025 and was still pursuing approval in August 2026. Pages saying Mexico approved tesofensine, "Tesomet" or "Nupenta" in 2023 are wrong. [12], [3], [104], [2], [68] See the dated legal-status summary.

Is tesofensine the same as Tesomet?

No. Tesomet is tesofensine combined with metoprolol, a beta-blocker added to cancel the rise in heart rate, and is being developed for hypothalamic obesity and Prader-Willi syndrome. Its trials show metoprolol can offset the heart-rate rise; they do not show that tesofensine alone is safe for the heart, and they found a loss of lean mass and some serious psychiatric events. [14], [56], [57], [33] See the Tesomet trials.

Can you take tesofensine with semaglutide or tirzepatide?

This combination has not been tested. Many people online take a small dose of tesofensine alongside a weekly GLP-1 injection, and community education groups disagree about whether that is sensible, particularly during a break from the injection. Neither drug's trials tell you what the combination does to weight, heart rate or mood. [46], [131], [7] See adding it to GLP-1 drugs and the guides to semaglutide and tirzepatide.

How long does tesofensine stay in your system?

Weeks. Its half-life is about 9 to 10 days and its main breakdown product's about 16 days, so it takes roughly six to seven weeks after the last dose for most of it to clear. After a single 483 mcg dose, anti-doping chemists could detect it or its breakdown products in urine for up to about three weeks. [7], [34], [29] See how long it lasts.

Is tesofensine stronger than phentermine or Ozempic?

No trial has compared them directly. In 2008 the TIPO-1 authors said 0.5 mg "might have the potential" to produce twice the weight loss of the obesity drugs approved at the time, but that was a 24-week comparison across separate trials. Semaglutide, the drug in Ozempic and Wegovy, has larger and longer trials behind it. [1], [125] See the comparison table.

Is it legal to buy tesofensine?

In every country and region checked for this guide, no approved tesofensine product exists. It is not FDA-approved, FDA lists it as ineligible for pharmacy compounding, and it is not approved in Mexico, Canada, Australia, the UK or the EU. A "research use only" label does not make a product legal or safe to use. [102], [36], [3], [105], [107], [110], [109], [106] See the dated legal-status summary.

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.

Animal study

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

Beta-blocker

A medicine that slows the heart by blocking the effect of adrenaline-like signals on it. Metoprolol, the second ingredient in Tesomet, is a beta-blocker.

Bioavailability

How much of a dose reaches the bloodstream in a usable form. For swallowed tesofensine it is more than 90%.

Cell study (in vitro)

Research on cells or purified proteins in a dish or test tube. It gives early clues about biology, but it is far from proof of an effect in people.

Compounding

When a pharmacy prepares a customized medicine from individual ingredients. In the US, federal rules control which bulk ingredients pharmacies may use, and FDA lists tesofensine as ineligible.

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 12 weeks. A cycle is a course plus a planned break before any further use.

CYP3A4

A liver enzyme that breaks down many medicines, including tesofensine. Drugs that block it can raise tesofensine levels.

Daily total

All the amounts taken in one day, added together. For example, 250 mcg twice daily is a 500 mcg daily total.

Dose (amount each time)

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

Expression of concern

A formal notice from a journal that serious questions have been raised about a published paper. It is not a retraction, but it warns readers to interpret the paper with care.

Food noise

An informal term for frequent, intrusive thoughts about food and eating. It is not a medical measurement.

GLP-1 drug

A medicine that copies or mimics GLP-1, a gut hormone that signals fullness, such as semaglutide, tirzepatide or orforglipron. Tesofensine is not a GLP-1 drug.

Half-life

The time it takes for the level of a substance in the blood to fall by half. For tesofensine it is about 9 to 10 days. It is not the same as how long an effect lasts.

Holter monitor

A small wearable heart monitor that records the heartbeat continuously, usually for 24 to 48 hours.

Hypomania

A period of abnormally elevated, energetic or irritable mood with less need for sleep. It is milder than mania but can still be serious.

Intravenous (IV)

Given directly into a vein, so it enters the bloodstream immediately.

Investigational

Still being studied and not approved by a regulator, such as the FDA, to treat any condition.

Lean mass

Everything in the body that is not fat, mostly muscle, organs, bone and water. Body scans measure it separately from fat.

Loading dose

A higher amount given for the first few days so that blood levels rise faster, followed by a lower daily amount.

mcg and mg

Micrograms and milligrams. 1 mg equals 1,000 mcg, so 0.5 mg is 500 mcg. Mixing them up can mean a 1,000-fold error.

Metabolite

A substance the body makes when it breaks down a drug. Tesofensine's main metabolite, NS2360 (M1), lasts longer but is much weaker.

Neurotransmitter

A chemical messenger that nerve cells use to signal each other, such as dopamine, noradrenaline or serotonin.

Oral

Taken by mouth and swallowed, as a tablet, capsule or liquid.

Orphan designation

A status the FDA gives to a drug being developed for a rare disease. It brings development incentives but is not an approval.

Peptide

A short chain of amino acids, the building blocks of proteins. Tesofensine is not a peptide.

Pharmacokinetics

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

Phase 3 trial

A large trial, usually the last stage before a company applies for approval, that tests whether a treatment works and how safe it is in the intended patients.

PHQ-9

A standard nine-question questionnaire used to screen for depression. Its last question asks about thoughts of self-harm.

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.

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.

Reuptake

The recycling step in which a nerve cell pulls a chemical messenger back in after releasing it. Blocking reuptake leaves more of the messenger active.

Serotonin syndrome

A potentially dangerous reaction to too much serotonin, usually from combining drugs that raise it. Signs include agitation, fever, sweating, shaking and a fast heartbeat.

Steady state

The point at which the amount of a drug taken each day equals the amount removed, so levels stop rising. It takes about five half-lives, roughly six to seven weeks for tesofensine.

Subcutaneous (SC)

Injected into the fatty layer just under the skin. Tesofensine has not been tested this way in people.

Tinnitus

Hearing ringing, buzzing or hissing that has no outside source.

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 tesofensine.

Explore more of the research

Go deeper into the animal and laboratory experiments behind the mechanism claims. These are preclinical studies: they explain how tesofensine might work, not what it does in people. Doses are given per kilogram of the animal's body weight and cannot be converted into human doses.

Across this guide, the citations include 28 original scientific papers, 10 of them animal or cell studies. The library below summarizes all 10. Paper counts are not counts of independent research teams, and registry records, reviews, websites and personal accounts are counted separately.

How this guide was researched

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

The guide cites 134 sources, including 28 original scientific papers. Each type of source answers a different question. Studies show what researchers measured. Protocol descriptions show how tesofensine 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