LGD-4033 vs Proviron

Moderate Research vs Well Studied
avoid Mechanism-based · 64% Both LGD-4033 and Proviron 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

LGD-4033 Proviron
Weight 338.25 Da 304.47 Da
Half-life ~24-36 hours ~12 hours
Type Nonsteroidal selective androgen receptor modulator (C14H12F6N2O) DHT derivative (C20H32O2)

Key Benefits

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
Proviron
01 Strong SHBG binding frees more circulating testosterone, enhancing TRT efficacy
02 Improved mood, motivation, confidence, and overall sense of well-being
03 Significant enhancement of libido and sexual function
04 Anti-estrogenic effect reduces the need for dedicated aromatase inhibitors
05 Harder, drier, more defined physical appearance without water retention
06 Minimal hepatotoxicity due to absence of 17-alpha alkylation
07 May improve sperm quality at low doses in subfertile men
08 Rapid onset of subjective well-being effects (often within days)

Side Effects

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)
Proviron
Accelerated hair thinning or loss in those predisposed to male pattern baldness (DHT-mediated)
Mild suppression of endogenous testosterone at higher doses (though less suppressive than most AAS)
Oily skin and increased sebum production
Mild HDL cholesterol suppression with extended use
Increased body hair growth
Contraindications
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)
Prostate cancer (active or history of androgen-sensitive prostate cancer)
Severe liver impairment (though hepatotoxicity risk is minimal)
Breast cancer in males
Hypersensitivity to mesterolone or any excipients
Women who are pregnant or may become pregnant (androgenic effects on fetus)

Research Evidence

LGD-4033 Proviron
Status Moderate Research Well Studied
References 5 studies 5 studies
Latest 2018
FDA Approved No No

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