When should I start PCT after my last Testosterone Enanthate injection?

This article references peer-reviewed clinical research and published literature. It is not medical advice.

Day 14 post-last-injection. That is the answer. The reasoning matters — it drives how you handle short esters, mixed cycles, and 19-nors with entirely different kinetics.

The kinetics

Testosterone Enanthate: t½ ≈ 4.5 days IM. Five half-lives to reach functional clearance. Serum concentrations at post-last-injection intervals:

  • Day 7: 50% of peak still circulating
  • Day 14: 25% — SERM signalling begins to register at the pituitary
  • Day 21: 6–12% — effectively baseline for recovery purposes

Starting SERMs at day 7 is wasted medication — the hypothalamus still reads suppressive androgen load and will not resume GnRH pulsing. Starting at day 21 leaves an additional week of HPTA inactivity before recovery stimulus arrives. Day 14 is the compromise the published protocols converge on.

Cypionate

t½ 8 days. The 14-day rule holds; some conservative protocols extend to day 16–18. The difference is negligible.

Short esters — Propionate, Trenbolone Acetate

Propionate t½ is 0.8 days. Clearance by day 3–4 post-last-injection. PCT begins day 3. Trenbolone Acetate matches the same window.

19-nor compounds — different game

Nandrolone Decanoate t½ is 15 days. Full clearance takes 75+ days. SERM-only PCT starting at day 14 is pharmacologically ineffective and widely reported as such in recovery bloodwork. For nandrolone cycles: either hCG 500 IU 2× weekly during the final 4 weeks of cycle (preserves testicular response volume) or delay SERM initiation to day 21–28, or both.

Protocol

Standard SERM recovery sequence:

  • Tamoxifen 40 mg/day × 2 weeks, 20 mg/day × 2 weeks — milder side profile, adequate for most moderate cycles
  • Clomiphene 50 mg/day × 4 weeks — aggressive LH signal, vision disturbance in 5–10% of users
  • Combined: tamoxifen 20 mg + clomiphene 50 mg daily × 4 weeks for longer or heavier runs

Confirmation bloodwork

Week 6 post-PCT: total T, free T, LH, FSH, estradiol (sensitive assay), SHBG. Total T below 400 ng/dL at this mark means incomplete recovery — extend SERM 2–4 weeks, retest. Below 300 ng/dL at week 12 post-PCT is the threshold at which clinical input is warranted; extended cycles of suppressive compounds can require hCG + SERM combined restart, not SERM monotherapy.

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