Tamoxifen: The Definitive Guide

What is tamoxifen?

Tamoxifen is a prescription tablet that blocks the effect of estrogen in some tissues, including the breast, while acting like estrogen in others. Doctors prescribe it mainly for breast cancer, in women and men. Men on testosterone therapy meet it when breast tissue grows or becomes tender, and sometimes as a way to raise their own testosterone. [1], [2], [3]

It belongs to a group called SERMs (selective estrogen receptor modulators). "Selective" is the key word: tamoxifen sits in the estrogen receptor, the docking site estrogen uses to switch on a cell, and blocks it in breast tissue but partly switches it on in other tissues. The US label calls it an "estrogen agonist/antagonist". It is not a steroid; the label describes it as a nonsteroidal agent. [2], [1]

Two things surprise many men. First, tamoxifen does not lower estrogen. It blocks estrogen's signal while blood estradiol rises: in oligospermic men (men with low sperm counts) the US label reports that LH, FSH, testosterone and estrogen all went up. Second, its only labeled use in men is breast cancer. The US tablet label says it is effective "in the treatment of metastatic breast cancer in women and men", and none of the current US, UK or Canadian labels lists gynecomastia or TRT. [4], [5]

It was first approved in the United States on December 30, 1977, as Nolvadex. [6]

[6], [7], [2], [8], [9], [10]

This guide also covers raloxifene (Evista), a related SERM approved for bone loss after menopause that some men use for the same breast symptoms. Its US label says it is not recommended in men (see raloxifene). [11]

Typical Tamoxifen Protocols

Most male studies and the AUA table use 10 or 20 mg once a day, or 10 mg twice a day. Two trials went higher: 30 mg a day in a fertility trial and 20 mg twice a day in a small trial in men with liver cirrhosis. The breast-cancer labels allow up to 40 mg a day. Courses for breast growth ran from 1 month to 1 year, and 20 mg daily is the most common single schedule. [1], [3], [14], [17], [18], [21], [22]

Titration Adjusting the dose

No label adjusts tamoxifen for men. When a SERM is used to raise testosterone, the AUA measures LH four weeks after starting if testosterone stays low. It considers a higher dose only if LH is still low or normal; a high LH points to failing testicles, where a higher dose is unlikely to help. In the bicalutamide trials, 20 mg a day prevented more breast symptoms than 10 mg (8.8% vs 23.5% of men had them at 6 months), and 20 mg once a week was clearly worse than 20 mg daily (74.4% vs 31.7% developed breast growth). [3], [23], [24]

Breaks and courses

Courses for breast growth in studies were time-limited, from 1 month to 1 year. Tamoxifen is not part of continuous TRT. When the cause keeps going, the benefit fades after tamoxifen stops: in the dose-response trial, breast symptoms became common in every group once tamoxifen ended while bicalutamide continued (what happens when you stop). [17], [14], [23]

Read the units. Tablets come as 10 mg or 20 mg. The US oral solution holds 20 mg in 10 mL, so 10 mg is 5 mL; the UK solution holds 10 mg in 5 mL. A 20 mg tablet once a day gives the same blood levels as a 10 mg tablet twice a day, according to the US label. The Canadian monograph says not to split the 20 mg tablet, so a 10 mg dose normally means a 10 mg tablet or measured liquid. No syringe arithmetic applies. [2], [9], [1], [13]

These doses come from breast-cancer labels, one guideline table and trials in men taking prostate cancer drugs or with unexplained breast growth. Prescribers choose the dose and course for each person. These guides are for men; testosterone therapy for women is covered in testosterone therapy for women.

Cautions for every schedule above. Tamoxifen raises the risk of blood clots in the legs and lungs, and the UK labels rule out its fertility use in anyone with a personal or family history of unexplained clots. Testosterone gel also raised vein clots slightly in the TRAVERSE trial (blood clots). It must not be taken with anastrozole, it strengthens the effect of warfarin, and it needs periodic blood counts and liver tests (monitoring). Before any course, breast growth on TRT is usually first managed by watching and adjusting the testosterone dose (what guidelines say). [12], [25], [1], [26], [3]

Where schedules differ: whether to use it at all, tamoxifen vs anastrozole, prevent vs treat, 10 vs 20 mg ↓

What is tamoxifen commonly used for in men?

Its one labeled use in men is breast cancer: the ASCO guideline for male breast cancer recommends tamoxifen for an initial five years when the cancer is hormone receptor-positive. Everything else in this guide is off-label use, and the evidence behind each use differs a great deal. [1], [32]

• Breast growth or tenderness (gynecomastia). The best evidence comes from men taking bicalutamide, an antiandrogen (a drug that blocks testosterone's action) for prostate cancer. Smaller studies cover other kinds of breast growth, including unexplained growth in adults.
• Raising testosterone without TRT. The AUA lists tamoxifen 20 mg daily as an alternative for men with low or low-normal LH, especially men who want to keep their fertility. Most of the research on this idea used clomiphene or enclomiphene instead.
• Fertility. Tamoxifen raises the pituitary hormones that drive sperm production, but pregnancy benefits are uncertain, and men's fertility guidelines give it a limited role.
• Recovery after stopping TRT or steroids ("post-cycle therapy"). Widely discussed online; no controlled study has isolated tamoxifen's effect.

[14], [17], [3], [33], [34], [29]

Does tamoxifen help gynecomastia (breast growth in men)?

Yes, in the settings where it has been tested, and most clearly in men on prostate cancer drugs. In a double-blind trial of 114 men taking bicalutamide, breast growth developed over 48 weeks in 73% on placebo, 10% on tamoxifen 20 mg daily and 51% on anastrozole 1 mg daily. Breast pain developed in 39%, 6% and 27%. Other randomized trials found the same pattern with 10 mg daily, and a 2025 meta-analysis found that tamoxifen cut the risk of breast growth and breast pain by about 82%, while anastrozole showed no significant benefit. [14], [15], [35], [36]

Outside prostate cancer care, the evidence is smaller. In a placebo-controlled crossover trial of 10 men, one month of 10 mg twice daily shrank the breast tissue in 7, only partly, and relieved pain in all 4 who had it. In a 2004 audit of 36 men aged 18 to 64 given 20 mg daily for 6–12 weeks, the lump resolved or improved to the man's satisfaction in 30. Firm "lump" tissue responded in every case, fatty tissue in 62.5%. In a series of 43 patients aged 12 to 62, mostly teenagers with breast growth during puberty, 6 months of 20 mg daily cleared the breast tissue in 26 (62%). It came back in 27% of those. Growths under 4 cm disappeared far more often than larger ones (90% vs 52%). [17], [18], [37]

What it does not do well is shrink long-standing, scarred (fibrous) tissue. In a 2023 comparison of 170 patients treated with tamoxifen or surgery, the authors concluded that surgery is better for the most advanced grade, and a high estrogen level predicted tamoxifen failure. Both European andrology guidelines send long-lasting breast growth to surgery. [38], [39], [31]

In teenagers, breast growth during puberty resolves on its own in more than 90% within 24 months, according to the European Academy of Andrology; treatment of adolescents is specialist care. [39]

Can tamoxifen treat gynecomastia caused by TRT?

It is sometimes prescribed for this, but no trial has tested it, and the major guidelines do not include it as a step. Breast symptoms are uncommon on TRT. In the trials the AUA reviewed, gynecomastia appeared in 1 of 73 men on a 50 mg gel, 3 of 78 on a 100 mg gel and none of 76 on a patch. Two of those four men already had it before treatment. A 2026 review found that only 17% of TRT trials even reported it. [3], [40]

What the guidelines actually say:

• AUA (US, 2018). Watch first, because "breast symptoms sometimes abate". If symptoms persist with high estradiol, lower the testosterone dose when the on-treatment level is upper-normal, or use an aromatase inhibitor when it is low or normal. There is no SERM step. [3]
• European Academy of Andrology (2019). Remove the cause and wait; no SERMs, aromatase inhibitors or non-aromatizable androgens for gynecomastia in general; surgery for long-lasting growth. [39]
• Italian Society of Andrology and Sexual Medicine (SIAMS, 2026). Drug treatment "may be considered in selected idiopathic or painful forms"; otherwise observation or surgery. [31]
• A 2025 practice review. "Low-dose tamoxifen" for symptomatic growth on TRT, with no dose given, and waiting when estrogen is not raised. [28]

The form of testosterone may matter more than any add-on. A 24-week trial compared a skin patch with injections every 2 weeks. The injections produced above-normal testosterone and estradiol for several days after each dose. Existing breast growth resolved in 4 of 10 men on the patch but only 1 of 9 on injections. [41] See estrogen on TRT for how estradiol behaves on each form.

Can tamoxifen raise testosterone instead of TRT?

It can raise testosterone in men whose testicles work, but it is not approved for low testosterone, and the evidence is about blood levels, not symptoms. By blocking estrogen's feedback in the brain, tamoxifen makes the pituitary release more LH and FSH. In an open-label study of 10 healthy men, two weeks of 20 mg daily raised testosterone by an average of 52%. In a randomized trial of 76 men with low sperm counts, 30 mg daily raised average testosterone from 4.9 to 7.9 ng/mL (about 490 to 790 ng/dL, or 17 to 27 nmol/L), against 5.3 to 5.6 ng/mL on placebo. [42], [21]

In a clinic series of 57 men treated for low sperm counts, 3 months raised median testosterone from 3.4 to 5.3 ng/mL (about 12 to 18 nmol/L), with no comparison group. [43]

It only works when the brain-to-testes chain is intact. The European urology guideline says SERMs "cannot work" in primary hypogonadism (failing testicles) or in secondary hypogonadism caused by damage to the pituitary or hypothalamus. The US infertility guideline adds that they will not help after pituitary surgery. [26], [33]

A rise in the number is not the same as feeling better. No trial of tamoxifen in men with low testosterone has measured symptoms. A 2020 review concluded that clomiphene and tamoxifen "should not be used in routine clinical practice" to treat sexual symptoms in men whose low testosterone comes from the brain or pituitary (central hypogonadism). Most of the SERM evidence for low testosterone comes from clomiphene and enclomiphene: a 2025 meta-analysis found they raised testosterone by about 274 ng/dL (about 9.5 nmol/L) more than placebo. See the clomiphene and enclomiphene guides. [44], [45], [46]

Does tamoxifen help fertility?

It raises the hormones that drive sperm production, but whether it leads to more pregnancies is uncertain. In men with low sperm counts, tamoxifen consistently raised LH, FSH and testosterone. Sperm results were mixed: one study found better sperm movement after 3 months, but an older study of 9 men and a randomized trial of 76 found no significant change in sperm counts. [5], [47], [21]

Reviews disagree. A Cochrane review found no difference in pregnancy rates in the trials with secure randomization (odds ratio 1.26, 95% confidence interval 0.99 to 1.56). A 2013 meta-analysis that pooled clomiphene and tamoxifen found higher pregnancy rates (odds ratio 2.42). A 2025 review could not pool tamoxifen against placebo at all. [48], [49], [50]

Guidelines split by situation:

• For infertile men with low testosterone, the AUA/ASRM guideline allows SERMs, hCG or aromatase inhibitors (Conditional; Grade C). [33]
• For unexplained infertility with normal testosterone, the same guideline says SERMs have "limited benefits" compared with assisted reproduction, and the European urology guideline says not to use them routinely. [33], [34]

Tamoxifen does not protect sperm production during TRT. The AUA/ASRM guideline calls the evidence for add-on medicines to testosterone "too limited to recommend", and testosterone should not be prescribed to men who want to conceive. An older trial combined tamoxifen with oral testosterone undecanoate (36 vs 11 pregnancies on placebo, among 106 couples each). It studied men with low sperm counts of unknown cause, not men with low testosterone, and is not a model for TRT. [33], [51] See TRT and fertility.

Is tamoxifen used after stopping TRT or steroids?

It is often used this way, but there is no controlled evidence that it speeds recovery. A review set out to do a meta-analysis on treating steroid-induced low testosterone and found that no quality studies qualified. A 2023 survey of 470 men linked post-cycle therapy to milder withdrawal symptoms but noted the practice "has no objective evidence of effectiveness". In a 2026 cohort of 79 recreational bodybuilders, clomiphene (not tamoxifen), alone or with hCG, sped up hormone recovery, but men who took nothing also recovered, and hormone levels were normal in every group by month 6. [29], [30], [52]

For men who need to recover sperm production, the European urology guideline advises stopping steroids for 6–12 months before trying SERMs or gonadotropins, and the VA says there is no standard protocol. Published recovery regimens after TRT are built around hCG, sometimes with a SERM added. See stopping TRT and hCG. [34], [53], [54]

How long does tamoxifen take to work for gynecomastia?

Pain usually eases before size changes. In the 6-month series, breast pain had gone in every patient by 3 months, and in the crossover trial one month already brought partial shrinkage. In a study of teenagers, measurable shrinkage began after the fourth month and continued to month 6. Tamoxifen itself takes about 4 weeks to reach steady levels, and its main breakdown product about 8 weeks. [37], [17], [55], [1]

Relapse is common when the cause persists or the course ends: 27% in the 6-month series, and 5 of 23 men in an older comparison with danazol. [37], [56]

The guide does not teach how to judge breast symptoms at home. The Academy note below covers a structured way to think them through before any add-on medicine.

Where do tamoxifen protocols differ?

Most of the disagreement is not about the dose. It is about whether tamoxifen belongs in the plan at all, and that depends on what caused the breast growth, how long it has been there and which guideline you read.

Should tamoxifen be used for gynecomastia at all?

The sources genuinely disagree, because they describe different men and different evidence.

[36], [39], [31], [3], [28]

The practical consequence: in prostate cancer care, where the cause cannot be removed, tamoxifen is a well-tested option. On TRT, where the cause is usually a changeable dose or form, guidelines start by changing the testosterone.

Tamoxifen or anastrozole for breast tissue?

In head-to-head trials, tamoxifen won. In men on bicalutamide, anastrozole 1 mg daily left 51% with breast growth versus 10% on tamoxifen; a systematic review found tamoxifen better than anastrozole, and a 2025 meta-analysis found no significant benefit from anastrozole at all. In boys with pubertal breast growth, anastrozole also failed against placebo. [14], [57], [58], [36], [59]

Yet the AUA's path for breast symptoms on TRT names aromatase inhibitors, not SERMs, while the VA's 2026 recommendations do not generally recommend aromatase inhibitors for men on testosterone, citing heart, belly-fat and bone concerns. The two approaches work differently: anastrozole lowers estradiol throughout the body, and a year of it lowered spine bone density in older men; tamoxifen leaves estradiol high and blocks it in breast tissue. They should not be taken together (interactions). [3], [53], [60] See the anastrozole guide.

Prevent it, or treat it once it starts?

In men starting bicalutamide, taking 10 mg daily from day one left fewer and milder breast symptoms than waiting and treating with 20 mg once symptoms began. Symptoms persisted in 27.7% after treatment, and treated symptoms that remained were more intense. [16]

On TRT, no guideline recommends preventive tamoxifen. Breast symptoms are uncommon on TRT and sometimes settle on their own, which makes a daily clot-raising drug for everyone hard to justify. [3], [39]

10 mg or 20 mg? Daily or less often?

In the only dose-finding trial (282 men on bicalutamide), breast symptoms at 6 months fell with each step up in dose: 96.7% on placebo, 86.2% on 1 mg, 60.0% on 2.5 mg, 55.3% on 5 mg, 23.5% on 10 mg and 8.8% on 20 mg. Hot flushes became more common from 5 mg upward. Other trials still found large benefits with 10 mg. [23], [15], [35]

Taking it less often did worse. In a randomized trial of 80 men, switching to 20 mg once a week after 8 weeks of daily dosing let breast growth develop in 74.4%, against 31.7% on 20 mg daily throughout. No study supports every-other-day or twice-weekly schedules, which appear online for "estrogen control". [24]

A SERM or TRT for low testosterone?

They are different strategies. A SERM asks working testicles to make more testosterone and keeps sperm production running; TRT replaces testosterone and switches both off. The AUA treats SERMs, tamoxifen included, as off-label options for men with low or low-normal LH, especially men who want fertility. The Canadian urology guideline lists them as off-label alternatives for men who want fertility. The Endocrine Society and the European Academy of Andrology say the evidence is weak (details). [3], [61], [62], [45]

What happens when you stop tamoxifen?

The drug leaves slowly, and what happens next depends on whether the original cause is still there. [1], [23]

• The drug itself. With a half-life of about 5–7 days, and about 14 days for its main breakdown product, tamoxifen takes weeks to clear. In one study, testosterone and SHBG were still raised 9 weeks after a course ended. [1], [12], [47]
• Breast symptoms. When the cause continues, they tend to come back: in the dose-response trial, breast symptoms were common in every group a year after tamoxifen stopped while bicalutamide continued. After treatment of unexplained breast growth, relapse rates of 27% and 5 of 23 have been reported. [23], [37], [56]
• Hormones. A tamoxifen-driven rise in testosterone depends on taking it; no study has followed men who used it long term for low testosterone after they stopped. Nothing suggests a taper is needed; labels give no tapering instructions. [1]

For stopping testosterone itself, see stopping TRT.

How do tamoxifen tablets, liquid and raloxifene compare?

Tamoxifen is swallowed, once or twice a day, and behaves the same whether taken as a tablet or liquid. What changes its effect more is how each person's liver converts it, and the medicines taken with it.

How long does tamoxifen last in the body?

After a 20 mg dose, blood levels peak at about 5 hours. The half-life is about 5–7 days, and the main breakdown product, N-desmethyltamoxifen, lasts about 14 days. Because of that long tail, steady levels take about 4 weeks for tamoxifen and about 8 weeks for the breakdown product. About 65% of a dose leaves the body within 2 weeks, mostly in the stool. [1], [12]

Food does not matter: the Soltamox label says it can be taken without regard to meals. [2]

Why does the liver enzyme CYP2D6 matter?

Tamoxifen is partly a "pro-drug". The liver turns a small share of it into endoxifen and 4-hydroxytamoxifen, which bind the estrogen receptor about 100 times more strongly than tamoxifen itself. The liver enzyme CYP2D6 makes that conversion. [2], [13]

People differ in how well CYP2D6 works. In a large US study of women with breast cancer, the label reports average endoxifen levels of 15.9 ng/mL in normal metabolizers and 5.6 ng/mL in poor metabolizers. Some antidepressants and other medicines block CYP2D6 (interactions). The labels say the effect of these differences on how well tamoxifen works "is not well established", and all the outcome data come from breast cancer, not breast growth in men. [2]

Raloxifene (Evista): how is it different?

Raloxifene is a related SERM approved for bone loss after menopause and for breast cancer risk reduction in women. Its US label says there is no indication for use in men and its use is not recommended. Men still discuss it for breast symptoms because of one study. [11]

What the evidence shows in men and boys:

• Breast growth. In a review of 38 teenagers' records (not randomized), a greater share had their breast tissue shrink by more than half on raloxifene (86%) than on tamoxifen (41%). The authors said more study was needed to confirm a true treatment effect. No trial has compared the two in adults. [64]
• Hormones. In healthy men aged 60 to 70, 120 mg daily for 3 months raised LH by 29%, FSH by 21%, testosterone by 20%, estradiol by 21% and PSA by 17%, with no clear benefit overall. In men with low sperm counts, the rise in LH and FSH was larger with tamoxifen than with raloxifene. [63], [20]
• Bone. In men receiving hormone-blocking treatment for prostate cancer, raloxifene 60 mg daily raised hip bone density by 1.1% while it fell by 2.6% without it. No similar bone study of tamoxifen in men was found. [65]
• Risks. Evista carries a boxed warning for blood clots and death from stroke, and its label says to stop it at least 72 hours before long periods of immobility, such as after surgery. Its half-life is about 28 hours. [11]

In Canada, the Evista brand was cancelled on January 30, 2026, while generic raloxifene remains marketed (checked September 2026). [66]

How should tamoxifen be stored?

Store it at room temperature and away from light. Each product's label sets its own details, so the leaflet in your box is the final word. [1], [2], [13]

[1], [2], [13]

What does tamoxifen do to fertility, estrogen and red blood cells?

Each of these has its own hub guide. Here is what is specific to tamoxifen.

Fertility. Tamoxifen raises LH and FSH, the opposite of testosterone therapy, but sperm counts often did not improve in trials, and it does not overcome the sperm shutdown caused by TRT (details above). See TRT and fertility. [4], [21], [33]

Estrogen. Tamoxifen raises estradiol in men. In 9 men with low sperm counts taking 10 mg daily, estradiol rose from 185 to 631 pmol/L (about 50 to 172 pg/mL) over 6 months. In a trial of men with breast cancer, median estradiol rose 67% in 3 months. For comparison, the AUA suggests referral to an endocrinologist when estradiol before TRT stays above 40 pg/mL (about 147 pmol/L). A high estradiol result while taking tamoxifen is expected and does not mean the drug has failed. See estrogen on TRT. [5], [67], [3]

Red blood cells. No study read for this guide measured tamoxifen's effect on hematocrit, so there is no basis for saying it raises or protects against it. The label reports falls in platelets and white cells in some patients. Men on TRT keep the usual hematocrit checks; see hematocrit on TRT. [1]

Doserly

What tamoxifen does to hormone results in men

LH rose

4.5 to 7.6 mIU/mL (median, 3 months)Paffenholz 2019, 57 men with low sperm counts

FSH rose

7.6 to 15.9 mIU/mL (median, 3 months)Paffenholz 2019

Testosterone rose

4.9 to 7.9 ng/mL (about 490 to 790 ng/dL; 17 to 27 nmol/L), 30 mg daily vs placebo 5.3 to 5.6Krause 1992, randomized, 76 men

Testosterone rose

+52% in 2 weeks on 20 mgBirzniece 2015, 10 healthy men

Estradiol rose

185 to 631 pmol/L (about 50 to 172 pg/mL) over 6 months on 10 mgWillis 1977, 9 men

Estradiol rose

+67% (median) at 3 monthsMALE trial 2021, men with breast cancer

SHBG rose

Significant rise; still raised 9 weeks after stopping (no number in abstract)Hampl 1988

IGF-1 fell

-24.8% in 2 weeksBirzniece 2015

An aromatase inhibitor lowers estradiol; tamoxifen does not.

Small human studies in different groups of men; direction and rough size only.

What do we actually know about tamoxifen in men?

A good deal about breast growth caused by prostate cancer drugs, a little about unexplained breast growth, hormones and fertility, and nothing from trials about breast growth caused by TRT.

What did the randomized trials in men find?

The bicalutamide trials and the five reviews that pool them are one body of evidence, not several independent confirmations. Every trial is also in older men with prostate cancer, whose breast growth comes from testosterone being blocked, while on TRT it comes from estradiol made from extra testosterone. The biology overlaps but is not the same. [58], [68], [69], [36], [70]

Doserly

Breast growth in the tamoxifen trials in men

Percent of men. All were taking bicalutamide for prostate cancer, not TRT.

Boccardo 2005: 114 men, 48 weeks

Breast growthBreast pain

Placebo

Breast growth 73%; breast pain 39%

Anastrozole 1 mg daily

Breast growth 51%; breast pain 27%

Tamoxifen 20 mg daily

Breast growth 10%; breast pain 6%

Fradet 2007: 282 men, breast growth or pain at 6 months

Placebo

96.7%

Tamoxifen 1 mg daily

86.2%

Tamoxifen 2.5 mg daily

60%

Tamoxifen 5 mg daily

55.3%

Tamoxifen 10 mg daily

23.5%

Tamoxifen 20 mg daily

8.8%

Breast events became common in all groups by 24 months, after tamoxifen stopped while bicalutamide continued.

Bedognetti 2010: 80 men, breast growth

20 mg daily throughout

31.7%

20 mg weekly after 8 weeks daily

74.4%

Men on bicalutamide for prostate cancer, not TRT. Source: randomized trials (abstracts).

What do the smaller studies add?

Studies of unexplained breast growth without a placebo group report high response rates. In a cohort of 81 men on 10 mg daily, 73 had a complete response. A records comparison with danazol (ages 13 to 82) found complete resolution in 18 of 23 patients on 20 mg against 8 of 20 on danazol, but all 5 relapses were on tamoxifen. Without a placebo group, some of that improvement may have happened anyway. In men with liver cirrhosis and breast pain, 14 of 16 had less pain or none during tamoxifen in a randomized crossover study. For teenagers, a 2013 systematic review found no randomized trials. [19], [56], [22], [71]

What is still unknown?

• Whether tamoxifen helps breast growth caused by TRT, and at what dose and for how long.
• Whether it improves symptoms, not just testosterone numbers, in men with low testosterone.
• Its long-term effect on bone in men; European urology guidance warns that long-term SERM use can reduce bone density. [26]
• Its effect on hematocrit.
• Long-term safety in men without cancer: a review of adverse events in men concluded that long-term studies are lacking. [72]

How does tamoxifen work?

Tamoxifen works by occupying the estrogen receptor, not by removing estrogen. [2]

In breast tissue, breast growth in men comes from glandular tissue that responds to estradiol. Tamoxifen competes with estradiol for the receptor, so gland cells receive a weaker growth signal even when blood estradiol is high. The US label describes this as competition with estrogen for binding to the receptor, reducing receptor-driven growth in breast tissue. [2], [1]

In the brain, the hypothalamus and pituitary use estradiol as a thermostat reading: when estradiol is high, they send less LH and FSH to the testicles. Tamoxifen blocks that reading, so the pituitary sends more LH and FSH, and working testicles make more testosterone. Some of that extra testosterone becomes estradiol, which is why estradiol rises too. The AUA describes tamoxifen as blocking estrogen's negative feedback at the hypothalamus and pituitary, and the European urology guideline adds that the effect needs an intact axis. [3], [33], [26]

Other effects. Tamoxifen raises SHBG (sex hormone-binding globulin, the protein that carries testosterone in the blood). In the Boccardo trial, free testosterone stayed unchanged on tamoxifen because SHBG rose. It also lowered IGF-1, a growth-hormone marker, by about 25% in healthy men. [47], [14], [42]

What are the risks and unanswered questions?

Is tamoxifen safe?

For a short, supervised course it is usually tolerated, but it has real risks that a TRT add-on should justify: blood clots, eye and liver effects, and side effects that lead many men to stop. Most of the male safety data come from men with breast cancer, who are older and take it for years. In those men, clot risk was highest in the first 18 months, so a short course does not avoid it. Long-term effects in men without cancer are unknown. [73], [74], [72]

What side effects do men report?

In three series of men taking tamoxifen for breast cancer:

• 24 men: 62.5% had at least one side effect: lower sex drive (29.2%), weight gain (25%), hot flashes (20.8%), mood changes (20.8%), depression (16.6%), insomnia (12.5%) and one leg clot. One in five (20.8%) stopped within a year because of side effects. [74]
• 38 men: half reported side effects, most often hot flashes (18.4%); 23.7% stopped. [75]
• 64 men: 53% had side effects, most often weight gain (22%) and sexual problems (22%); 20.3% stopped, 4 of them because of clots. [76]

The US label adds that loss of libido and impotence have led men to stop. In contrast, a randomized trial found sexual function and quality of life unchanged on tamoxifen alone, and a review found few side effects in men treated for infertility or unexplained breast growth, with under 5% stopping overall. Adherence in men with breast cancer falls over time: only 64.6% were still taking it after a year in one study. [4], [67], [72], [77]

Does tamoxifen cause blood clots?

Yes, it raises the risk. In a cohort of 218 men with breast cancer (median age 69), clots occurred in 21 of 177 men on tamoxifen (11.9%) and 1 of 41 not taking it. That is about 52 versus 22 per 1,000 person-years. Most clots (81%) happened in the first 18 months, and men over 71 were at higher risk. [73]

The US label reports rates from the large US prevention trial in women. Pulmonary embolism (a clot in the lungs) occurred at 0.75 versus 0.25 per 1,000 women-years on placebo. Deep vein thrombosis occurred at 1.26 versus 0.79 (30 vs 19 cases), a difference that did not reach statistical significance. The European urology guideline says men should be warned of the possible clot risk with SERMs. Leg pain or swelling, sudden breathlessness or chest pain need urgent care. [1], [26]

Testosterone adds a small clot signal of its own. TRAVERSE, a randomized trial in about 5,200 men aged 45 to 80 with heart disease or high heart risk, compared daily testosterone gel with a placebo gel. Among the 2,596 men on testosterone and the 2,602 on placebo:

• Heart attack, stroke or heart death: 7.0% vs 7.3% (hazard ratio 0.96), which met the trial's safety margin. [78], [25]
• Clots in veins: 1.7% vs 1.2%, including pulmonary embolism in 0.9% vs 0.5%. [25]
• Heart rhythm and kidneys: atrial fibrillation (an irregular heartbeat) 3.5% vs 2.4%; acute kidney injury (a sudden drop in kidney function) 2.3% vs 1.5%. [25]

Its limits: it tested only a gel, the average man used it for 21.7 months, and about 61% stopped their study gel early. Nothing read for this guide measured how the clot risks of tamoxifen and testosterone combine. See TRT and heart health. [78], [25]

What does the boxed warning say?

The US boxed warning is headed "For Women with Ductal Carcinoma in Situ (DCIS) and Women at High Risk for Breast Cancer". DCIS is an early breast cancer confined to the milk ducts. The warning covers uterine cancers, stroke and pulmonary embolism when tamoxifen is used in that setting (US labels, checked September 2026). The uterine risks do not apply to men; the clot risk has been seen in men too, as the cohort above shows. [4], [1]

What about the eyes, liver and blood counts?

• Eyes. The label reports changes to the cornea, reduced color vision, a clot in a retinal vein and damage to the retina, plus more cataracts and cataract surgery. In one study of women, five or more years of use raised the risk of cataracts. Any change in vision needs checking. [1], [79]
• Liver. Tamoxifen can change liver enzymes and, rarely, cause fatty liver, hepatitis or worse. [1]
• Blood counts. Falls in platelets and white cells have been reported. [1]

Is tamoxifen legal? Is it FDA approved?

Checked September 2026. Rules differ by country and change often.

• United States. Tamoxifen is FDA-approved as a prescription medicine for breast cancer; generic tablets and Soltamox solution are marketed, and the Nolvadex brand is discontinued. It is not a controlled substance; its label carries no controlled-substance schedule. Every use discussed here for men without breast cancer is off-label, and the AUA marks it not FDA-approved in men for low testosterone. FDA's drug shortage data list no tamoxifen or raloxifene shortage (updated September 26, 2026). [6], [7], [3], [80]
• Canada. Prescription-only. APO-TAMOX and TEVA-TAMOXIFEN are marketed; Nolvadex-D was cancelled on March 22, 2023 and Tamofen in January 2011. Canadian labeling covers breast cancer in women only. The Evista brand of raloxifene was cancelled on January 30, 2026; generics remain. [10], [13], [66]
• United Kingdom. Tablets and an oral solution are licensed for breast cancer and, in women, for infertility caused by lack of ovulation. Nolvadex 20 mg is still listed; the 10 mg strength is discontinued. [12], [8], [9]
• Australia. Tamoxifen is listed on the Pharmaceutical Benefits Scheme only for hormone receptor-positive breast cancer. Australian product information could not be checked for this guide. [81]

Buying tamoxifen labeled "for research use only" does not make it legal, tested or the same as a licensed medicine.

Is tamoxifen banned in sport?

Yes. Tamoxifen, raloxifene and clomiphene are anti-estrogenic substances in class S4.2 of the World Anti-Doping Agency (WADA) Prohibited List, banned in and out of competition, and the 2027 list keeps them banned from January 1, 2027. [82], [83]

Who should be especially cautious?

• Anyone with a past blood clot, a clotting disorder or a family history of clots. The UK labels rule out its fertility use in these people, and clots were the most common reason men stopped in one breast cancer series. [12], [76]
• Men over about 70. Clot risk was higher in men over 71. [73]
• People with liver disease or eye problems, given the label warnings. [1]
• Men who have had depression. Low mood and depression were among the commonest side effects in men. [74]
• Men taking warfarin, anastrozole or antidepressants that block CYP2D6 (see the next question).
• Men with failing testicles (primary hypogonadism). Tamoxifen cannot raise testosterone there. [26]
• Teenagers. Pubertal breast growth usually settles on its own; any treatment is specialist care. [39]
• Drug-tested athletes. Banned at all times. [82]
• Women who are or may become pregnant. Tamoxifen can harm an unborn baby; these guides are for men. [2]

Can tamoxifen be taken with other medicines?

The labels list several interactions that matter to men on TRT:

• Anastrozole: do not combine. The US label says tamoxifen "should not be coadministered with anastrozole", and UK labels list it as a contraindication. In the large ATAC breast cancer trial, the combination worked no better than tamoxifen alone. Taking both also lowered anastrozole levels by 27%, a drop the researchers judged unlikely to matter clinically. Tamoxifen also lowered letrozole levels by 37–38%. [4], [84], [12], [85]
• Warfarin and similar blood thinners. The anticoagulant effect can rise significantly; the label advises careful monitoring of clotting times, and it is a contraindication for women using tamoxifen to reduce breast cancer risk. [1], [2]
• Medicines that block CYP2D6, such as paroxetine, fluoxetine, bupropion, quinidine and cinacalcet. The UK label says to avoid strong inhibitors whenever possible; the US label says their effect on how well tamoxifen works is not well established. A pharmacogenetics guideline for breast cancer advises avoiding moderate and strong inhibitors, and found that raising the dose to 40 mg does not bring poor metabolizers to normal endoxifen levels. [12], [2], [86], [87]
• Rifampin (an antibiotic for tuberculosis). It lowered tamoxifen exposure by 86%. [1]

Testosterone itself is not listed as an interaction. Bring a full list of everything you take, including supplements, to a pharmacist or prescriber.

What should be monitored while taking tamoxifen?

The labels ask for periodic blood counts, including platelets, and periodic liver tests, and for prompt checks of any vision change or clot symptoms. The AUA adds hormone checks when a SERM is used to raise testosterone. Use this summary to prepare questions for your prescriber; it is not a personal testing plan. [1], [2], [3]

[1], [2], [26], [3], [74]

For men also on TRT, the usual checks continue unchanged; see TRT blood work. When a tamoxifen course starts or stops, note the date next to any lab result: in one study, testosterone and SHBG stayed raised for 9 weeks after a course ended. [47]

What do people in public communities report?

Public forums hold every kind of tamoxifen story: tender nipples that settled, lumps that did not shrink, and men who stopped because of how it made them feel. The accounts below come from public Reddit threads posted between September 2025 and September 2026, described without identifying anyone. Threads about non-prescribed steroid cycles appear only where they show something about tamoxifen itself, and are marked.

What do men describe when it is prescribed for breast symptoms on TRT?

Most stories start early in treatment. One man felt nipple sensitivity within days of starting 125 mg of testosterone a week, split into injections every other day. His doctor prescribed tamoxifen 20 mg daily for 14 days, then 10 mg. He felt good for the first two weeks, but then his sex drive fell while his estradiol climbed from 55 to 210 pmol/L, and he could not tell whether tamoxifen or the hormone changes were responsible. A month in, his energy was rising, his nipples were still sensitive, and he planned to discuss a lower testosterone dose after his next blood test. [88]

Another man developed burning nipples and small lumps after switching from gel to injections. He started tamoxifen and exemestane (an aromatase inhibitor), felt horrible on the exemestane, and by week 4 of tamoxifen most of the lumps had gone, though burning and swelling still came and went. He had also lowered his testosterone dose and split it into three injections a week, so two things changed at once. [89]

A man on 100 mg a week with a small hard lump was prescribed tamoxifen 20 mg daily for 4 weeks plus exemestane twice a week, and planned to start the tamoxifen alone for fear of low-estradiol symptoms. [90]

Some courses have no clear end. A 20-year-old with breast tissue that predated his treatment for secondary hypogonadism described taking tamoxifen alongside TRT for months, because his nipple sensitivity came back whenever he stopped. [91]

Does it always work?

No. The reports match the studies: pain and tenderness often ease before any lump shrinks, and firm, older tissue may not shrink at all.

• Pain gone, lump unchanged. After a two-month non-prescribed cycle, one man took 20 mg daily, then 30 mg; nearly two months later the tenderness had resolved, but the lump was the same size. (Steroid cycle.) [92]
• Partial shrinkage, then surgery. A man on TRT with many hormone changes said 40 mg a day halved his breast tissue over two months, but enough remained that he had it removed surgically. [93]
• No response. A man not on TRT, who had already had breast surgery once, noticed no improvement in a painful lump after two months of 20 mg daily. With later medicine changes the tissue grew, and he was careful not to blame tamoxifen for the growth. [94]

What unwanted effects come up?

Mood effects are the most striking. A man with a history of depression, who had earlier felt better on clomiphene, described brief good spells on doctor-directed tamoxifen followed by severe depression with suicidal thoughts, plus weight gain and food cravings; he told his doctor. Thoughts of suicide need urgent help, whatever the cause. [95]

• Anxiety within hours. Coming off long-term testosterone, one man twice had severe anxiety, low mood and shakiness within hours of a 10 mg morning dose; taking it at night was more tolerable. He also noticed vision problems that improved after he stopped. (His history included higher-dose steroid use.) [96]
• Brain fog and sleep. Another man, 11 days into 20 mg after stopping self-administered testosterone, described brain fog, poor appetite, broken sleep and severe anxiety that eased when he skipped a dose and returned on 10 mg; he planned to see a doctor. [97]
• Sex drive and erections. Lower sex drive appears in several threads, but almost always alongside a testosterone or hormone change, as in the first story above. [88], [98]
• Worry about the eyes. Vision comes up often. One man asking about preventive use said reports of lasting vision problems made him hesitate; another chose a low tamoxifen dose because clomiphene had left him with floaters that never went away. [99], [100]

Does tamoxifen lower estrogen? The most common mix-up

Many threads start from the belief that tamoxifen lowers estradiol, and replies often correct it. [101]

• One man, after five years on 100 mg a week, said an online TRT clinic proposed doubling his dose to 200 mg a week and adding tamoxifen twice weekly because of an estradiol result of 53, drawn four days after an injection. Replies questioned raising the dose when his levels were already high, and explained that tamoxifen is not an aromatase inhibitor. [102]
• An endocrinologist recommended 10 mg daily for 60 days to a man with an estradiol result of 82 and chest tension that came and went; a reply noted that tamoxifen blocks estrogen's effects without lowering the number. [103]
• A man taking tamoxifen after a steroid cycle found his estradiol and LH above the reference range while testosterone had recovered, which is the pattern the drug is expected to produce. (Steroid cycle.) [104]

Do people take it to prevent breast growth, or with an aromatase inhibitor?

Yes, and replies usually push back, citing side effects and clot risk. [99], [105]

Combinations with aromatase inhibitors are common, despite the labels. One man was prescribed weekly hCG, nightly anastrozole, tamoxifen every other morning and daily tadalafil at once, and many replies questioned starting tamoxifen and anastrozole together. Another objected to TRT refills that bundled tamoxifen and anastrozole he was not using. [106], [107]

What do people report after stopping TRT?

• Recovery, with a confounder. One man came off about a year of TRT with hCG and then tamoxifen, had several weeks of low energy, and gradually regained libido and energy. He had varicocele surgery in the same period and had not yet had blood tests. [100]
• No sperm, and a hard few months. A man who stopped TRT to try for a baby learned that a semen sample taken before stopping showed no sperm. After 4 weeks of tamoxifen and 6 weeks of hCG he stopped everything, and three months later described fatigue, very low libido and depression while waiting for his fertility team. [108]
• Symptoms returned. A man who stopped after a few months of TRT and took tamoxifen afterwards found his old low energy and anxiety gradually came back, and planned to restart TRT. [109]

Others weighed tamoxifen as an alternative to starting TRT at all. One man with low testosterone and low-normal LH said his urologist first suggested tamoxifen, but he preferred clomiphene because of joint pain he had been told tamoxifen might worsen. [110]

How can you judge a tamoxifen story?

Ask: Was it prescribed, and for what: tender nipples, a firm lump, prevention or recovery? What dose, and for how long? What else changed at the same time, such as the testosterone dose, injection frequency, an aromatase inhibitor, hCG or a steroid cycle? Was the lump examined or imaged, and was estradiol measured, and when relative to the last injection? What happened a few months after stopping?

These selected discussions show what people experience and the questions research should answer. They are not a survey of all users, a success rate or a substitute for the studies.

How does tamoxifen compare with other options?

These are the medicines most often weighed against tamoxifen by men on TRT. Status was checked in September 2026.

The practical differences between these medicines are what each does to estradiol, bone and clots, and whether it can be combined with the others. Changing the testosterone dose or form, and surgery for long-standing tissue, are options every guideline discusses before or alongside any of them. [3], [39] See estrogen on TRT.

Common questions about tamoxifen

Does tamoxifen lower estrogen?

No. It blocks estrogen's action in breast tissue and at the brain, while blood estradiol usually rises, by 67% in 3 months in one trial of men. Lowering estradiol itself is what an aromatase inhibitor does, with its own risks. [67], [5] See estrogen.

Can I take tamoxifen while on TRT?

Prescribers sometimes do prescribe it, off-label, for breast growth or tenderness. Its evidence comes from men on prostate cancer drugs. The AUA's path for breast symptoms on TRT does not include it, and the European Academy of Andrology recommends against SERMs for gynecomastia in general. Guidelines start by watching and adjusting the testosterone dose or form. [3], [39] See gynecomastia on TRT.

Can tamoxifen and anastrozole be taken together?

No. The US label says they should not be coadministered, and UK labels list the combination as a contraindication. In a large breast cancer trial, taking both worked no better than tamoxifen alone. They also pull in different directions: anastrozole lowers estradiol, while tamoxifen raises it. [4], [84], [12] See interactions.

How long does tamoxifen take to work for gynecomastia?

Pain usually eases first: it had gone in every patient by 3 months in one series, while shrinkage was still being measured at 6 months. Firm, recent tissue under 4 cm responds best, and relapse is common when the cause continues. [37], [17] See how long it takes.

Tamoxifen or raloxifene for breast growth?

There is no fair comparison in adults. One review of teenagers' records found more shrinkage with raloxifene, but it was not randomized, and the Evista label says raloxifene is not recommended in men. Tamoxifen has the randomized evidence, from men on prostate cancer drugs. [64], [11], [14] See raloxifene.

Does tamoxifen cause blood clots?

Yes, it raises the risk. In a cohort of men with breast cancer, 11.9% of those on tamoxifen had a clot, mostly in the first 18 months, and the risk was higher over age 71. Anyone with a history of clots should raise it with the prescriber before starting. [73], [12] See blood clots.

Should I have a CYP2D6 test before taking tamoxifen?

It is not routine outside breast cancer care. Poor CYP2D6 metabolizers make much less endoxifen, and a breast cancer pharmacogenetics guideline uses the test to guide therapy. But the labels say the effect on how well tamoxifen works is not well established, and no study has tested it for breast growth in men. Avoiding medicines that block CYP2D6 is the more practical step. [2], [86] See CYP2D6.

Is tamoxifen a steroid? Is it a controlled substance?

No to both. It is a nonsteroidal prescription medicine and not a controlled substance in the US or Canada, but it is banned in sport at all times. [1], [6], [10], [82] See legal status.

Glossary

Plain explanations of the medical, 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.

Antiandrogen

A medicine that blocks testosterone's action on its receptor, such as bicalutamide for prostate cancer. Breast growth is a common side effect.

Aromatase inhibitor

A medicine, such as anastrozole, that blocks the enzyme that turns testosterone into estradiol, so estradiol falls. Tamoxifen is not one.

Boxed warning

The most serious type of warning on a US drug label, printed in a box at the top. Tamoxifen's covers uterine cancers, stroke and lung clots in women.

Cohort study

A study that follows a group of people over time and records what happens to them. Without random assignment, other differences between people can explain some results.

Confidence interval

The range within which the true result probably lies. A 95% confidence interval for an odds ratio that includes 1 means the study cannot rule out no effect.

Controlled substance

A medicine that the law restricts beyond an ordinary prescription because it can be misused, such as testosterone in the US. Tamoxifen is not one.

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.

Crossover trial

A trial in which each person takes both the treatment and the comparison (often a placebo) in turn, so each serves as their own comparison.

CYP2D6

A liver enzyme that turns tamoxifen into its most active forms. How well it works varies between people and can be blocked by some medicines, such as paroxetine and fluoxetine.

Endoxifen

A breakdown product of tamoxifen, made by CYP2D6, that binds the estrogen receptor about 100 times more strongly than tamoxifen itself.

Estradiol

The main form of estrogen. In men it is made mostly from testosterone, and it rises when tamoxifen raises testosterone.

Estrogen receptor

The docking site inside a cell that estrogen binds to switch the cell's response on. Tamoxifen occupies it and blocks estrogen in breast tissue.

FSH (follicle-stimulating hormone)

A pituitary hormone that supports sperm production. Tamoxifen raises it; testosterone therapy lowers it.

Gynecomastia

Growth of breast tissue in men, often tender at first. It is linked to a higher estrogen-to-testosterone balance.

Half-life

The time it takes for the level of a substance in the blood to fall by half. For tamoxifen it is about 5–7 days, and about 14 days for its main breakdown product. It is not the same as how long an effect lasts.

Hazard ratio

How often an event happens in one group compared with another over time. A hazard ratio of 1 means no difference; 0.96 means about 4% fewer events.

Hematocrit

The share of the blood made up of red blood cells. Testosterone therapy can raise it, which is why it is checked.

Hypogonadotropic hypogonadism

Low testosterone because the brain and pituitary send too little LH and FSH to the testicles. Also called secondary hypogonadism. SERMs can only help if the pituitary itself still works.

Idiopathic

Of unknown cause. Idiopathic gynecomastia is breast growth for which no cause is found.

LH (luteinizing hormone)

A pituitary hormone that tells the testicles to make testosterone. Tamoxifen raises it; testosterone therapy switches it off.

Meta-analysis and systematic review

A systematic review gathers all studies on a question in a planned way. A meta-analysis combines their results statistically.

Odds ratio

A way of comparing how likely an outcome is in two groups. An odds ratio of 1 means no difference; above 1 means the outcome was more likely in the treated group.

Off-label use

Prescribing an approved medicine for a use, dose or group of people that its label does not cover. It is legal for prescribers but means the regulator has not reviewed evidence for that use.

Oligozoospermia

A low sperm count in a semen sample.

Post-cycle therapy (PCT)

Drugs taken after an anabolic-steroid cycle to try to speed the return of the body's own testosterone, usually SERM tablets and sometimes hCG. The schedules used online have not been tested in trials.

Person-years

A way of counting time in a study: one person followed for one year is one person-year. Rates per 1,000 person-years allow for people being followed for different lengths of time.

Placebo

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

Primary hypogonadism

Low testosterone because the testicles themselves do not work well, even though the pituitary sends plenty of LH and FSH. Tamoxifen cannot raise testosterone here.

Raloxifene

A SERM (brand name Evista) approved for bone loss after menopause. Its US label says it is not recommended in men.

SERM (selective estrogen receptor modulator)

A tablet, such as tamoxifen, raloxifene, clomiphene or enclomiphene, that blocks estrogen's action in some tissues and mimics it in others. At the brain it blocks estrogen's feedback, so the pituitary releases more LH and FSH.

SHBG (sex hormone-binding globulin)

A blood protein that carries testosterone. Testosterone bound to it is not immediately available to tissues. Tamoxifen raises it.

Steady state

The point, after repeated doses, when the amount taken in each day matches the amount cleared, so blood levels stop climbing. For tamoxifen it takes about 4 weeks.

Titration

Adjusting a dose in steps, usually based on blood tests and symptoms.

TRT (testosterone replacement therapy)

Prescribed testosterone, by injection, gel or other forms, for men with low testosterone. It switches off the brain's LH and FSH signals.

Venous thromboembolism (VTE)

A blood clot in a vein, usually in the leg (deep vein thrombosis), which can travel to the lungs (pulmonary embolism).

WADA

The World Anti-Doping Agency, which publishes the list of substances banned in sport. Tamoxifen and other SERMs are banned at all times.

Weekly total

All the amounts taken in one week, added together. For example, 20 mg once a day is a 140 mg weekly total.

How this guide was researched

This guide is built from a thorough review of the sources cited throughout it: product labels from the United States, the United Kingdom and Canada, clinical guidelines from the United States, Canada, the United Kingdom and Europe, published clinical trials and studies, and regulatory records. We also reviewed public online forums where men describe their own experiences with tamoxifen and raloxifene.

The guide cites 112 sources, including 12 product labels, 12 clinical guidelines and 41 original studies in people, plus 23 public community threads. Each type of source answers a different question. Labels and guidelines show what is approved and what clinicians are told to do. Trials and studies show what was measured, and in whom. 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