The prescription foundation of male HRT — how TRT works, what clinical dosing looks like, and how to find a qualified provider who actually runs the right labs.
Testosterone replacement therapy (TRT) restores testosterone levels in men with clinically low production. The two most common injectable esters are testosterone cypionate (Depo-Testosterone) and testosterone enanthate (Delatestryl) — functionally interchangeable, with slightly different release kinetics.
TRT is a prescription medication in the US, classified as a Schedule III controlled substance. It should only be used under the supervision of a licensed provider who has confirmed clinically low testosterone through repeated labs and appropriate symptom evaluation.
FDA approved (Schedule III). Prescription only. WADA prohibited (S1 — Anabolic Agents). StackTrax does not sell or facilitate purchase of TRT.
Exogenous testosterone binds androgen receptors throughout the body — muscle, bone, brain, fat, skin. Drives the anabolic and masculinizing effects.
The cypionate / enanthate ester slows release from the injection depot. Cypionate has a slightly longer half-life (~8 days) vs enanthate (~5 days) — functionally similar at weekly or twice-weekly injections.
Exogenous testosterone signals the hypothalamus to stop producing LH and FSH, which shuts down the testes’ own testosterone and sperm production. This is why TRT usually reduces fertility and testicular size — and why HCG is often added to preserve both.
Some testosterone converts to estradiol via the aromatase enzyme. Too little or too much estradiol both cause problems. Many patients don’t need an AI; those who do use low-dose anastrozole under a provider’s guidance.
TRT has decades of clinical use and is one of the most-studied hormonal therapies. The benefits are consistent when testosterone is actually low and the therapy is done properly.
| Benefit | Evidence |
|---|---|
| Energy & mood | Most reliable; improvements in low-T patients by 4–8 weeks |
| Libido & erectile function | Strong improvements at restored levels; less effective if vascular ED is the root cause |
| Lean mass & strength | Significant gains over 3–12 months at therapeutic levels |
| Bone density | Long-term elevation improves BMD; important in older men |
| Insulin sensitivity | Improvements in metabolic syndrome markers |
| Cognition | Modest improvements in spatial/verbal memory at restored levels |
Build your protocol, log every dose, monitor your body's response, and get reminders so you never miss a dose.
Start Tracking FreeDose is personalized. Your provider titrates based on trough labs, symptoms, and side effects. Note: weekly or twice-weekly dosing is a modern practice to smooth peak-to-trough levels — historically, cypionate / enanthate were dosed every 2–3 weeks (PMID 19011287), though that schedule often leaves levels out of the physiological range >50% of the time. More frequent injections are the reason your provider is likely choosing weekly or twice-weekly.
IM vs. SubQ — actual PK differences: PMID 34694927 showed that 100 mg/week IM testosterone cypionate produced significantly greater rises in estradiol, hematocrit, and PSA compared to SubQ testosterone enanthate autoinjector at the same dose, due to supraphysiological testosterone peaks with IM. Route choice should factor into how closely these labs are monitored, and may influence whether an AI, phlebotomy, or urology workup becomes necessary.
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Testosterone Replacement (Cypionate / Enanthate) is a prescription medication. StackTrax does not sell, prescribe, or facilitate purchase of prescription drugs.
Find a clinician who can order baseline lab work, screen for contraindications, monitor your response, and adjust dosing over time. Options to consider:
Before starting, you’ll typically want:
Avoid sources that offer prescription medications without labs, medical history, or licensed-provider oversight. If a telehealth service promises a prescription after a 5-minute questionnaire, that’s a red flag.
Build your protocol, log every dose, monitor your body's response, and get reminders so you never miss a dose.
Start Tracking FreeDisclaimer: This guide is for educational and informational purposes only and is not intended as medical advice, diagnosis, or treatment. The compounds discussed are not FDA approved for human use. Always consult a qualified healthcare provider before starting any new supplement or peptide protocol. StackTrax does not sell peptides or supplements directly — purchase links go to third-party vendors. StackTrax is not responsible for the products, quality, or business practices of any third-party vendor. This page contains affiliate links — StackTrax may earn a commission on purchases at no extra cost to you.
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