Testosterone Cypionate for TRT & Hormone Optimization — Anabolic Steroids

The most widely prescribed testosterone ester for replacement therapy with an 8-day half-life and flexible dosing.

Overview

Testosterone Cypionate is the most commonly prescribed form of testosterone replacement therapy (TRT) in the United States. It is an esterified form of testosterone with a half-life of approximately 8 days, allowing for weekly or biweekly intramuscular or subcutaneous injections. The cypionate ester is attached to the 17-beta hydroxyl group, slowing release from the injection depot. In February 2025, the FDA removed cardiovascular black box warnings following the TRAVERSE trial, and a December 2025 expert panel recommended removing prostate cancer warnings. At physiological replacement doses (100-200mg/week), it restores serum testosterone to the 350-650 ng/dL range, improving muscle mass, bone density, libido, mood, cognitive function, and metabolic health. It is the gold standard for male hypogonadism treatment.

Indications

  • Primary and secondary hypogonadism in males
  • Age-related testosterone decline (andropause)
  • Testosterone deficiency with symptoms (low libido, fatigue, depression)
  • Muscle wasting and sarcopenia
  • Osteoporosis in testosterone-deficient males
  • Gender-affirming hormone therapy (FTM)
  • Metabolic syndrome with concurrent low testosterone
  • Post-surgical or trauma-related androgen deficiency

Mechanism of Action

Low serum testosterone (<300 ng/dL) with symptoms: fatigue, decreased libido, depression, muscle loss, cognitive decline

Dosing

CompoundDoseFrequencyNotes
Testosterone Cypionate100-200 mgOnce weeklyStandard TRT replacement dosing to restore physiological levels (350-650 ng/dL)
Testosterone Cypionate50-100 mgTwice weekly (split dose)More stable blood levels with less peak-trough variation
Testosterone Cypionate150-200 mgEvery 14 daysLess frequent but greater peak-trough fluctuation

Evidence Grade

GRADE A

Safety & Contraindications

  • Schedule III controlled substance - prescription required
  • Monitor hematocrit - discontinue or reduce dose if >54%
  • Contraindicated in prostate cancer (under review as of 2025)
  • Contraindicated in breast cancer in males
  • May cause polycythemia - therapeutic phlebotomy may be needed
  • Monitor PSA levels in men over 40
  • Can suppress spermatogenesis and fertility - counsel patients
  • Cardiovascular black box warning removed by FDA in February 2025
  • May worsen sleep apnea - screen before initiating
  • Transference risk with topical forms - not applicable to injections
  • Monitor liver function periodically
  • Can cause gynecomastia via aromatization - may require AI adjunct