TRT: formulations & doses

Testosterone cypionate or enanthate are the workhorses — typically ~50–100 mg weekly, or 100–200 mg every two weeks, injected into muscle or under the skin. Weekly (or more frequent, smaller) dosing gives steadier levels and fewer peak-and-trough swings than fortnightly. Evidence ●●●●●

Testosterone undecanoate (Aveed) is a long-acting injection given roughly every 10 weeks, but it carries a boxed warning for serious pulmonary-oil-microembolism and anaphylaxis reactions, so it's given under a restricted program with a 30-minute observation after each dose.

Gels are applied daily and titrated to level — with a boxed warning about skin-to-skin transfer to women and children. Patches are daily (more skin irritation). Pellets are implanted under the skin every 3–6 months. Newer oral testosterone undecanoate (Jatenzo, Tlando) is taken twice daily with food; nasal and buccal forms also exist. Each suits a different preference for convenience, steadiness and cost.

The goal is to restore a mid-normal level — roughly 400–700 ng/dL (Endocrine Society), with the AUA aiming for the middle tertile, ~450–600 ng/dL — not to push levels high. Because different formulations peak at different times, the blood test is timed to the form (midway between injections for short-acting shots; after at least a week on a gel; at trough for long-acting). Chasing supraphysiologic numbers is where the risks climb.