Enclomiphene vs P21
Side-by-side comparison of key properties, dosing, and research.
GLP-1 / Weight Loss Agonists
EnclomipheneCognitive EnhancementAnti-Aging & Longevity
P21- Summary
- Enclomiphene is the trans-isomer of clomiphene citrate, a selective estrogen receptor modulator (SERM) that stimulates endogenous testosterone production by blocking estrogen negative feedback on the hypothalamus and pituitary. Unlike TRT, it restores testosterone while preserving or increasing sperm production and testicular volume.
- P21 is a synthetic peptide derived from CNTF (ciliary neurotrophic factor) that promotes hippocampal neurogenesis, enhances memory and spatial learning, and may reduce amyloid-beta pathology. It is used as a neurogenic and cognitive enhancer with potential anti-Alzheimer's applications.
- Half-Life
- 5-7 days (long half-life; accumulates)
- Not well characterized; likely short, but neurogenic effects persist long after administration
- Admin Route
- Oral
- SubQ, Intranasal
- Research
- —
- —
- Typical Dose
- 12.5-25 mg per day
- 100–500 mcg
- Frequency
- Once daily or every other day
- Once daily
- 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)
- Promotes hippocampal neurogenesis
- Enhances spatial memory and learning
- Increases BDNF expression
- Reduces amyloid-beta plaque formation (animal models)
- Anti-tau pathology potential
- Cognitive enhancement without stimulant effects
- Potential therapeutic for Alzheimer's and cognitive aging
- Side Effects
- Visual disturbances (rare but class-related SERM effect)
- Mood changes or irritability
- Hot flashes
- Elevated estradiol in some users
- +2 more
- Generally well tolerated in animal studies
- Limited human clinical data
- Injection site reactions
- Potential mild fatigue at initiation
- Stacks With
- —
- —