Exemestane vs LGD-4033
FDA Approved vs Moderate Research
avoid Mechanism-based · 64% Both Exemestane and LGD-4033 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
Exemestane LGD-4033
Weight 296.40 Da 338.25 Da
Half-life ~24 hours ~24-36 hours
Type Steroidal aromatase inhibitor (irreversible, suicide inhibitor) Nonsteroidal selective androgen receptor modulator (C14H12F6N2O)
Key Benefits
Exemestane
01 Irreversible aromatase inactivation eliminates estrogen rebound upon discontinuation
02 Steroidal structure with mild androgenic activity may offset some low-estrogen side effects
03 Potent estrogen suppression (85-95% reduction in estradiol at full dose)
04 Compatible with tamoxifen (unlike anastrozole, no pharmacokinetic interference)
05 Prevents gynecomastia during testosterone or aromatizable steroid cycles
06 Reduces estrogen-driven water retention, bloating, and blood pressure elevation
07 Oral dosing with once-daily or less frequent administration for cycle support
LGD-4033
01 Strongest SARM for lean muscle mass accrual, with clinical trial data supporting dose-dependent increases in lean body mass
02 Tissue-selective action with minimal stimulation of the prostate and other androgen-sensitive tissues
03 Clinical evidence of improved physical function (leg press strength, stair-climbing speed) in hip fracture patients
04 No aromatization to estrogen (no estrogen-related water retention or gynecomastia at the receptor level)
05 No conversion to DHT (reduced risk of androgenic hair loss and prostate stimulation compared to testosterone)
06 Convenient once-daily oral dosing due to 24-36 hour half-life
07 Phase 2 clinical data available, providing a stronger evidence base than most other SARMs
Side Effects
Exemestane
Joint pain and stiffness (generally less severe than with anastrozole due to mild androgenic activity)
Fatigue and general malaise
Hot flashes or flushing
Mood changes (irritability, flat affect, low mood)
Headache
Increased sweating
LGD-4033
Testosterone suppression (dose-dependent; more suppressive than Ostarine at equivalent doses, occurs in most users by week 4-6)
Water retention (non-estrogenic mechanism, typically mild to moderate, contributes to scale weight increase)
HDL cholesterol reduction (dose-dependent lipid impact observed in clinical trials)
Headaches (most common in the first 1-2 weeks, usually transient)
Fatigue or lethargy (related to testosterone suppression, typically becomes noticeable mid-cycle)
Reduced libido (related to HPG axis suppression, severity varies by dose and individual)
Contraindications
Known hypersensitivity to exemestane or any excipients
Premenopausal women (not indicated and potentially harmful to reproductive function)
Pregnancy or breastfeeding (teratogenic risk)
Severe hepatic impairment
Pre-existing severe osteoporosis or high fracture risk
Concurrent use with other aromatase inhibitors (anastrozole, letrozole)
Pre-existing liver disease or elevated liver enzymes at baseline
Hormone-sensitive cancers (prostate cancer or other androgen-driven malignancies)
Pregnancy or potential pregnancy (teratogenic risk from androgen receptor agonism)
Breastfeeding
Age under 25 (incomplete endocrine system maturation and higher risk of HPG axis disruption)
Concurrent use of hepatotoxic medications without medical supervision
Known cardiovascular disease (insufficient long-term safety data for this population)
History of significant lipid abnormalities (LGD-4033 suppresses HDL)
Research Evidence
Exemestane LGD-4033
Status FDA Approved Moderate Research
References 5 studies 5 studies
Latest — 2018
FDA Approved Yes No
This comparison is for educational and research purposes only. Consult a healthcare professional before use.