Side effects of methyltestosterone: a full review of the risks
Methyltestosterone is one of the oldest orally active anabolic-androgenic steroids, a chemically modified form of testosterone designed to survive digestion. Once used more widely in medicine, it has fallen out of favour largely because of its toxicity, especially to the liver. The editorial team provides a full, honest review of its side effects and the reasons it is now rarely prescribed, with no guidance on use.
What methyltestosterone is
Methyltestosterone is testosterone with an added methyl group at the 17-alpha position of the molecule. This small chemical change has a large consequence: it allows the steroid to resist breakdown in the liver when taken by mouth, making it orally active, unlike plain testosterone which is largely destroyed before reaching the bloodstream.
This 17-alpha-alkylation is the defining feature of a whole family of oral anabolic steroids. It solved the practical problem of oral dosing, but it created a new one, because the same property that protects the drug in the liver also makes it stressful and potentially toxic to that organ.
Historically, methyltestosterone was used for hormone replacement and various conditions, but safer alternatives — particularly modern testosterone preparations given by injection, gel or patch — have largely replaced it. Today its legitimate use is very limited, and it survives mainly in older formulations and, unfortunately, in the anabolic steroid grey market.
Because it is both an androgen and a 17-alpha-alkylated oral steroid, methyltestosterone carries the side effects of testosterone excess and the specific toxicity of the oral steroid class. Reviewing these together gives a full picture of why it is regarded as a poor choice.
Liver toxicity: the central concern
The most serious and characteristic risk of methyltestosterone is liver toxicity. The 17-alpha-alkyl structure that makes it orally active also makes it hepatotoxic, and this class of oral steroids is associated with a range of liver injuries more than almost any other.
Documented liver problems linked to 17-alpha-alkylated steroids include cholestasis, in which bile flow is impaired and jaundice develops; elevated liver enzymes signalling cell damage; and, with prolonged use, rare but grave conditions such as peliosis hepatis, where blood-filled cavities form in the liver, and liver tumours. These are not theoretical; they are reported in the medical literature.
| Liver condition | Nature | Severity |
|---|---|---|
| Raised liver enzymes | Marker of cell stress/damage | Common, usually reversible |
| Cholestasis | Impaired bile flow, jaundice | Serious |
| Peliosis hepatis | Blood-filled liver cavities | Rare, potentially fatal |
| Liver tumours | Benign or malignant growths | Rare, severe |
The risk rises with dose and duration, and because the liver handles so much of the body's chemistry, its injury has wide consequences. This hepatotoxicity is the single biggest reason methyltestosterone has been abandoned in favour of non-oral testosterone, which bypasses this first-pass liver burden entirely.
Anyone who has taken such a drug and develops abdominal pain, jaundice, dark urine or unusual fatigue needs prompt medical assessment, as these can signal liver harm.
Cardiovascular and metabolic harms
Beyond the liver, methyltestosterone shares the cardiovascular risks of anabolic steroids and, in some respects, amplifies them. Oral 17-alpha-alkylated steroids are particularly notorious for worsening the blood lipid profile, sharply lowering protective HDL cholesterol and raising harmful LDL, a combination that promotes atherosclerosis over time.
Other cardiovascular concerns include raised blood pressure, fluid retention and, as with androgens generally, increased red blood cell production that can thicken the blood and raise clotting risk. Long-term anabolic steroid use is associated with changes to the heart muscle and with a higher burden of cardiovascular disease.
Methyltestosterone can also affect blood sugar handling and, through fluid retention, burden the heart in susceptible people. These metabolic effects compound the direct cardiovascular ones, making the overall risk to the circulatory system substantial with sustained use.
Because these harms develop silently over time, they are easy to underestimate. The absence of immediate symptoms does not mean the cardiovascular system is unaffected, which is part of why unsupervised use is so hazardous.
Hormonal and virilising effects
As a potent androgen, methyltestosterone suppresses the body's own hormone production through negative feedback, reducing natural testosterone, shrinking the testes and impairing fertility in men. Recovery after stopping is not guaranteed and can be prolonged. It can also convert to oestrogenic activity, contributing to breast tissue growth in men.
In women, the androgenic effects are especially problematic and often irreversible. Virilisation includes deepening of the voice, growth of facial and body hair, enlargement of the clitoris, menstrual disruption and male-pattern hair loss. Some of these changes, notably the voice change, do not reverse when the drug is stopped, making androgen exposure particularly consequential for women.
- Men: suppressed natural testosterone, testicular shrinkage, reduced fertility, possible breast tissue growth.
- Women: voice deepening, facial hair, menstrual disruption, some changes permanent.
- Skin and hair: acne, oily skin, accelerated male-pattern baldness in susceptible people.
- Mood: irritability, aggression and mood swings reported with androgen excess.
These effects follow directly from the drug's androgenic nature and are shared, in varying degree, across anabolic steroids. The combination of irreversible virilisation in women and fertility suppression in men makes methyltestosterone a drug with lasting potential consequences.
The psychological effects deserve mention too: androgen excess has been linked to mood disturbance and, on withdrawal, to low mood and depression, adding a mental-health dimension to the physical risks.
Why it is rarely used, and the honest conclusion
The sum of these side effects — serious liver toxicity, adverse cardiovascular changes, hormonal suppression and virilisation — explains why methyltestosterone has been largely abandoned by modern medicine. Where testosterone replacement is genuinely needed, clinicians use non-oral forms that avoid the liver burden and allow steadier, safer hormone levels.
This history carries a clear message. A drug discarded by medicine because of its toxicity is not a sensible choice for self-directed use in sport or body-building, where doses are often far higher than any medical use and monitoring is absent. The grey-market supply adds the further hazards of unknown contents and dosing.
This article intentionally gives no information on how to take methyltestosterone, because there is no safe self-directed regimen and because its risk profile argues against use outside the narrowest medical circumstances. The responsible message is one of caution and honest risk disclosure.
Anyone considering or using such substances, and anyone experiencing symptoms after use, should seek medical advice. Readers may also find our overviews of liver protection, of cardiovascular risk from anabolic steroids, and of recovering natural hormone production useful further reading.
Conclusions of the editorial team
Methyltestosterone is an old oral anabolic steroid whose 17-alpha-alkyl modification makes it orally active but also hepatotoxic. Liver injury — from raised enzymes to rare but grave conditions — is its central and defining risk.
It also worsens cholesterol and cardiovascular risk, suppresses natural hormone production, and causes virilising effects in women that can be permanent, alongside mood disturbances.
These harms are precisely why modern medicine has largely abandoned it in favour of safer testosterone preparations. There is no safe self-directed use, and anyone affected by such substances should seek medical assessment rather than rely on grey-market products.
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- Nieschlag E, Vorona E. Mechanisms in endocrinology: medical consequences of doping with anabolic androgenic steroids. Eur J Endocrinol. 2015;173(2):R47-R58.
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- szteroidcsomag.com
