Compound · enclomiphene
T2Pharmaceutical

Enclomiphene

Trans-isomer of clomiphene citrate, acting as a selective estrogen receptor modulator (SERM) at the hypothalamus. Blocks estrogen negative feedback on GnRH neurons, increasing pulsatile LH and FSH release from the anterior pituitary. Unlike zuclomiphene (the cis-isomer), enclomiphene has no significant estrogenic agonist activity, resulting in cleaner testosterone elevation without the visual or mood side effects of racemic clomiphene.

Half-life
10 hours
Bioavailability
~50% (oral, estimated)
Route
oral
Evidence tier
T2 — Single-RCT or mechanistic
Optimization pillars
muscle · recovery
References
3 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
6.25–12.5 mg/day
Low-dose HPTA support
moderate
12.5–25 mg/day
Standard testosterone restoration
aggressive
25–50 mg/day
Clinical trial dosing
Monitoring
  • total-testosterone
  • free-testosterone
  • lh
  • fsh
  • estradiol
  • shbg
Contraindications
  • liver-disease
  • undiagnosed-vaginal-bleeding
  • pituitary-tumor
  • primary-hypogonadism
References
  • PMID:24717915Enclomiphene citrate stimulates testosterone production while preventing oligospermiaJ Urol, 2014
  • PMID:27105355Testosterone therapy in men with hypogonadism: an Endocrine Society clinical practice guidelineJ Clin Endocrinol Metab, 2018
  • PMID:26109534Nasal testosterone gel restores serum testosterone levels while maintaining sperm countsJ Sex Med, 2015
Notes

Enclomiphene solves the central problem of clomiphene therapy. Racemic clomiphene is a 50/50 mix of two molecules with opposing effects. Zuclomiphene is an estrogen agonist with a 30-day half-life that accumulates and causes visual disturbances, emotional blunting, and paradoxical estrogen activity. Enclomiphene is the pure antagonist with a 10-hour half-life. Clean in, clean out. The FDA never approved it despite multiple Phase III trials because of regulatory complications, not efficacy failures. Tier 2 reflects that regulatory limbo. The pharmacology is Tier 1 quality. The availability is not.

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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