Testosterone Cypionate is a long-acting esterified form of testosterone and the most commonly prescribed androgen in the United States. It serves as the foundational compound in nearly all anabolic steroid cycles due to its ability to maintain physiological testosterone levels and support anabolic processes.
Notes
Testosterone Cypionate is the gold standard base compound. It should be included in virtually every cycle to maintain physiological androgen levels even when running other suppressive compounds. An AI (aromatase inhibitor) such as anastrozole should be kept on hand. HCG at 250IU 2-3x/week during cycle helps maintain testicular function and makes PCT recovery smoother.
Testosterone Cypionate binds to the androgen receptor (AR) in target tissues, initiating transcription of androgen-responsive genes that promote protein synthesis and nitrogen retention in skeletal muscle. Once injected, esterase enzymes in the bloodstream cleave the cypionate ester, releasing free testosterone. This free testosterone also undergoes 5-alpha reduction to dihydrotestosterone (DHT) in androgen-sensitive tissues and aromatization to estradiol via the aromatase enzyme in adipose tissue. The androgenic and anabolic effects are mediated through both direct AR activation and secondary signaling pathways including IGF-1 upregulation in muscle and liver.
Following intramuscular injection, Testosterone Cypionate forms a depot in the muscle tissue from which it is slowly absorbed into the bloodstream. Peak serum testosterone levels are typically reached within 24-48 hours post-injection, with a gradual decline over 8-12 days corresponding to the cypionate ester half-life. The compound is metabolized primarily in the liver via oxidation and conjugation, with metabolites excreted in urine. Steady-state concentrations are generally achieved after 4-5 half-lives (approximately 5-6 weeks of consistent dosing). The long ester allows for less frequent injection schedules while maintaining relatively stable blood levels.
Typical Dose
150-200mg/week (TRT), 300-500mg/week (beginner cycle), 500-750mg/week (intermediate), 750-1000mg/week (advanced)
Frequency
2x per week (e.g., Monday/Thursday) for stable blood levels; once weekly is acceptable for TRT
Administration
Intramuscular injection (gluteal, deltoid, or vastus lateralis)
Half-Life
8-12 days
Contraindications
Begin PCT approximately 14 days after last Testosterone Cypionate injection to allow the ester to clear. Standard PCT: Nolvadex (tamoxifen) 20mg/day for 6 weeks, or Clomid (clomiphene) 50mg/day for 4 weeks then 25mg/day for 2 weeks. Some protocols combine both at half doses. If hCG was used on-cycle, taper it off before starting SERMs. Bloodwork 4-6 weeks after completing PCT to confirm recovery of LH, FSH, and total testosterone.