Testosterone
The main male sex hormone, given as injections (cypionate, enanthate), gels or pellets to men with low testosterone and symptoms.
FDA-approved for male hypogonadism; a Schedule III controlled substance in the US.
Used for
- Low testosterone with symptoms (TRT)
- Libido and sexual function
- Mood, energy, anemia and bone density in low-T men
- Low-dose transdermal use in postmenopausal women with low desire (off-label)
How it works
Acts on androgen receptors in muscle, bone, brain and sex organs, and converts to estradiol and DHT. Outside testosterone switches off LH and FSH, so the testes make less of their own and far less sperm.
Half-life: cypionate about 8 days, enanthate about 4.5 days (into the muscle)
What the research shows
- The Testosterone Trials (790 older men, 1 year, gel): improved sexual function and mood modestly and corrected anemia; no gain in walking or energy.
- TRAVERSE (5,246 men at high heart risk): no increase in heart attacks or strokes vs placebo, but more atrial fibrillation, blood clots in the lungs and acute kidney injury.
- The Endocrine Society recommends treating only men with symptoms and low levels on two early-morning tests.
- For women, the 2019 Global Consensus found good evidence only for low sexual desire after menopause, using doses near a tenth of a male dose; long-term safety data are lacking.
Dosing
Dosing isn’t listed on the public site. In the app, each published option is shown with its source (a drug label, a clinical guideline, a trial or community reports) and can be turned into a protocol you review.
Work out the units to draw for your vial →Side effects
- Higher hematocrit (thicker blood)
- Acne, oily skin
- Lower sperm count and smaller testes
- Fluid retention
- Breast tenderness if estradiol runs high
Cautions
- Stops sperm production in most men: plan for fertility (hCG, enclomiphene) before starting if you want children.
- For men: check hematocrit, PSA, estradiol and lipids on bloodwork; hold or lower the dose if hematocrit goes above 54%.
- For women: too high a dose can cause acne, unwanted hair growth, a deeper voice and a larger clitoris, some of which do not reverse. Never use it in pregnancy.
- Not with untreated prostate or breast cancer, or untreated severe sleep apnea.
- Prohibited in tested sports (WADA).
Storage
Unmixed or unopened: Vial at room temperature (20–25 °C), protected from light.
From the Testosterone cypionate label.
Interactions
Androgens can make oral blood thinners work more strongly; the blood-thinner dose may need lowering.
In diabetes, testosterone’s metabolic effects can lower blood sugar and so the insulin needed.
Not a full list. Tell your doctor and pharmacist everything you take.
Reference only, not medical advice. Written for this app from the cited research. Doses marked community-reported are not from trials.