Enclomiphene

Key Benefits#

• Restores testosterone to normal range without exogenous androgen administration
• Preserves or increases sperm production and fertility
• Maintains testicular volume (unlike TRT which causes testicular atrophy)
• LH and FSH levels rise, indicating intact HPG axis function
• Option for hypogonadal men desiring fertility
• Oral administration (no injection required)

Mechanism of Action#

Enclomiphene competitively antagonizes estrogen receptors in the hypothalamus and anterior pituitary, blocking the negative feedback of estradiol on GnRH and LH/FSH secretion. This disinhibition increases pulsatile GnRH release, elevating LH and FSH. The resulting LH surge stimulates Leydig cells to produce testosterone, while FSH maintains Sertoli cell function and spermatogenesis. The trans-isomer is isolated from racemic clomiphene to avoid the estrogenic effects of the cis-isomer (zuclomiphene).

Dosing Protocols#

Side Effects#

• Visual disturbances (rare but class-related SERM effect)
• Mood changes or irritability
• Hot flashes
• Elevated estradiol in some users
• Headache
• Nausea

Contraindications#

Estrogen receptor-positive cancersLiver disease (hepatic metabolism)Thrombotic disorders or hypercoagulable statesPregnancy (teratogenic risk)Combined with aromatase inhibitors may cause excessive estradiol suppression

Storage#

Store at room temperature in original container away from moisture and heat. No refrigeration required.

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