Enclomiphene vs MK-677
Well Studied vs Well Studied
avoid Mechanism-based · 64% Both Enclomiphene and MK-677 carry hepatotoxic risk. Combining hepatotoxic compounds significantly increases liver damage potential. If unavoidable, include liver support (TUDCA/NAC) and monitor ALT/AST frequently.
Molecular Data
Enclomiphene MK-677
Weight 405.96 Da 624.77 Da
Half-life ~10 hours ~24 hours
Type Trans-isomer of clomifene (selective estrogen receptor modulator) Non-peptide ghrelin receptor agonist
Key Benefits
Enclomiphene
01 Raises endogenous testosterone by stimulating the HPTA axis
02 Preserves fertility and spermatogenesis (unlike exogenous testosterone)
03 No estrogenic agonist activity (unlike racemic clomifene/Clomid)
04 Oral dosing with no injections required
05 Does not suppress the HPTA or cause testicular atrophy
06 Effective for post-cycle therapy and secondary hypogonadism
07 Well-tolerated with a favorable side effect profile
MK-677
01 97% increase in 24-hour growth hormone secretion
02 40-72% elevation in IGF-1 levels
03 Enhanced sleep quality with improved REM patterns
04 Preferential lean tissue gains of 1.1-2.7kg over 8-12 months
05 15% basal metabolic rate increase within 2 weeks
06 Oral administration (no injections required)
Side Effects
Enclomiphene
Headache
Nausea or mild gastrointestinal discomfort
Hot flashes or flushing
Mood changes (irritability or emotional sensitivity)
Fatigue during initial adjustment
MK-677
Appetite stimulation (>50% of users)
Water retention (30-40%)
Lethargy (20-30%)
Fasting glucose elevation (5-15mg/dL)
Note on testosterone suppression: at doses up to 20 mg daily, MK-677 is unlikely to cause significant testosterone suppression on its own. Above 20 mg daily, the likelihood of suppression and other side effects (insulin resistance, water retention, lethargy) increases. The case report documenting 85.7% testosterone suppression involved co-administration with LGD-4033, a SARM known to be profoundly suppressive, making the SARM the likely primary driver of that suppression.
Contraindications
Known hypersensitivity to clomifene or enclomiphene
Pre-existing liver disease or significantly elevated liver enzymes
Active or history of thromboembolic disorders
Pregnancy or women who may become pregnant (teratogenic risk)
Primary hypogonadism (testicular failure -- enclomiphene requires functional testes)
Pituitary tumors or undiagnosed pituitary pathology
Heart disease or congestive heart failure
Diabetes or pre-diabetes
Active cancer
Severe cardiovascular disease
Pregnancy or breastfeeding
Research Evidence
Enclomiphene MK-677
Status Well Studied Well Studied
References 5 studies 7 studies
Latest — July 2024
FDA Approved No No
This comparison is for educational and research purposes only. Consult a healthcare professional before use.