PCT

Post-Cycle Therapy is a pharmacological protocol targeting HPTA restoration after exogenous-androgen suppression. The goal is return to endogenous testosterone production and spermatogenesis — not maintenance of serum testosterone values through the transition.

Standard SERM-based protocol (4 weeks):

– Tamoxifen (Nolvadex): 20 mg/day weeks 1–2, then 10 mg/day weeks 3–4.
– OR Clomiphene (Clomid): 50 mg/day weeks 1–2, then 25 mg/day weeks 3–4.

Both SERMs occupy estrogen receptors at the hypothalamus and pituitary without agonist activity, lifting the negative-feedback brake on GnRH pulsing. LH and FSH rise; Leydig cells respond with testosterone synthesis; Sertoli cells resume spermatogenesis.

Tamoxifen vs clomiphene — the choice is not cosmetic:

Clomiphene is a 60:40 racemic mixture of enclomifene (pure antagonist, the therapeutic fraction) and zuclomifene (weak partial agonist with a serum half-life exceeding 14 days). The zuclomifene residue accumulates across a 4-week course and produces the documented visual-disturbance signature — phosphenes, transient colour shifts — and the mood effects clinicians attribute to “clomid fog.” Pure enclomifene is available in some markets (Androxal, EnclomOne) and avoids the accumulation entirely. Tamoxifen lacks the isomer problem and is the cleaner choice for most protocols.

Timing — start PCT when exogenous compound has cleared enough for the pituitary to register the hypogonadal state:

– After short esters (propionate, acetate): 3–5 days post-last-injection.
– After long esters (enanthate, cypionate): 14 days post-last-injection.
– After decanoate (Deca, Sustanon): 21–28 days post-last-injection.
– After oral-only cycle: 24–48 hours post-last-dose.

Starting SERM while residual ester is still hydrolysing is dose wasted. The SERM cannot lift a feedback brake that exogenous hormone is still pressing.

The Leydig-desensitisation trap:

Extended suppression (>16 weeks) produces Leydig-cell desensitisation to LH signalling. SERM restarts central signalling, but the testicular response is blunted — post-PCT bloodwork shows elevated LH with inadequate total T. The intervention is preventive: on-cycle hCG 500 IU 2× weekly throughout suppression maintains Leydig responsiveness. Post-cycle rescue with hCG is available but recovers less cleanly than prevention. Nandrolone-containing cycles produce the deepest suppression; multi-year trenbolone use produces the longest documented recovery timelines (12+ months, with or without aggressive PCT).

Bloodwork schedule:

Week 4 of PCT — LH, FSH, total testosterone, free testosterone, sensitive estradiol (LC-MS/MS, not immunoassay), SHBG. Week 8 retest if values have not normalised. Total T below 400 ng/dL with detectable LH at week 8 suggests ongoing recovery; below 300 ng/dL with suppressed LH is the threshold for clinical review.

Published recovery timelines: 3–6 months for moderate testosterone-only cycles, 6–12 months for nandrolone-containing protocols, 12+ months for multi-compound multi-year use. The recovery distribution is right-skewed — the median user hits baseline faster than the mean. Plan around the mean.