Compound · clomiphene
T1serms_ais

Clomiphene (Clomid)

Mixed estrogen receptor modulator composed of two geometric isomers: enclomiphene (trans, ~62%) and zuclomiphene (cis, ~38%). Enclomiphene drives the anti-estrogenic activity at the hypothalamus, increasing GnRH and gonadotropin release. Zuclomiphene is a weak estrogen agonist with a much longer half-life, accumulating during extended use and potentially causing estrogenic side effects.

Half-life
5 days (enclomiphene), 30 days (zuclomiphene)
Bioavailability
~90% (oral)
Route
oral
Evidence tier
T1 — Multiple RCTs
Optimization pillars
muscle · recovery
References
4 peer-reviewed
Dose ranges

Three tiers ordered by aggressiveness. Tier chips on every OPTIMIZE intervention let you filter the catalog by your evidence tolerance.

conservative
12.5–25 mg/day
Monotherapy for secondary hypogonadism
moderate
25–50 mg/day
Standard PCT
aggressive
50–100 mg/day
PCT loading (first week only)
Monitoring
  • total-testosterone
  • free-testosterone
  • estradiol
  • lh
  • fsh
  • shbg
  • lipid-panel
  • igf-1
Contraindications
  • liver-disease
  • undiagnosed-uterine-bleeding
  • ovarian-cysts
  • visual-disturbances-history
References
  • PMID:15476432Clomiphene citrate effects on testosterone/estrogen ratio in male hypogonadismJ Sex Med, 2004
  • PMID:25264335Clomiphene citrate and testosterone gel replacement therapy for male hypogonadismJ Sex Med, 2014
  • PMID:26323089Clomiphene citrate and enclomiphene for late onset hypogonadismJ Urol, 2015
  • PMID:29506718A review of clomiphene citrate for the treatment of male hypogonadismTher Adv Urol, 2018
Notes

Clomiphene is a blunt instrument. The two-isomer problem is real — enclomiphene does the work you want, zuclomiphene accumulates and causes the side effects you do not. Visual disturbances, emotional volatility, estrogenic rebound. Every negative PCT experience someone attributes to clomid is almost certainly zuclomiphene accumulation. The drug works for HPTA restart. It just brings baggage. Understanding the isomer pharmacokinetics is the difference between a clean PCT and a miserable one.

This is not medical advice

Discuss with a licensed clinician before starting, stopping, or changing any compound. This page documents what the research literature describes — it is not a prescription.

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