MK-677 vs Raloxifene

Well Studied vs FDA Approved
avoid Mechanism-based · 64% Both MK-677 and Raloxifene 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

MK-677 Raloxifene
Weight 624.77 Da 473.58 Da
Half-life ~24 hours ~28 hours
Type Non-peptide ghrelin receptor agonist Benzothiophene-derived selective estrogen receptor modulator

Key Benefits

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)
Raloxifene
01 Superior breast tissue estrogen receptor antagonism makes it the preferred SERM for gynecomastia reversal
02 No estrogen agonist activity in the uterus, avoiding the endometrial risks associated with tamoxifen
03 Estrogen agonist activity in bone preserves bone mineral density and reduces fracture risk
04 Lower overall thromboembolic risk compared to tamoxifen
05 Metabolized via glucuronidation rather than CYP2D6, avoiding the drug interaction concerns that affect tamoxifen
06 Simple once-daily oral dosing with a manageable 28-hour half-life
07 FDA-approved with decades of clinical safety data in postmenopausal women

Side Effects

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.
Raloxifene
Hot flashes and increased sweating
Leg cramps and muscle spasms
Joint pain or stiffness
Peripheral edema (mild swelling in extremities)
Flu-like symptoms during initial weeks
Contraindications
Heart disease or congestive heart failure
Diabetes or pre-diabetes
Active cancer
Severe cardiovascular disease
Pregnancy or breastfeeding
History of deep vein thrombosis, pulmonary embolism, retinal vein thrombosis, or other venous thromboembolic events
Active or past history of stroke or transient ischemic attack
Known hypersensitivity to raloxifene hydrochloride or any excipients
Pregnancy or planned pregnancy (category X -- contraindicated)
Prolonged immobilization (e.g., post-surgical recovery, extended bed rest) due to elevated DVT risk
Severe hepatic impairment

Research Evidence

MK-677 Raloxifene
Status Well Studied FDA Approved
References 7 studies 4 studies
Latest July 2024
FDA Approved No Yes

This comparison is for educational and research purposes only. Consult a healthcare professional before use.