LGD-4033 vs Ondansetron
Moderate Research vs FDA Approved
avoid Mechanism-based · 64% Both LGD-4033 and Ondansetron 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 Ondansetron
Weight 338.25 Da 293.36 Da
Half-life ~24-36 hours ~4 hours
Type Nonsteroidal selective androgen receptor modulator (C14H12F6N2O) Carbazole derivative (C18H19N3O)
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
Ondansetron
01 Highly effective at controlling nausea and vomiting from a wide range of causes, including GLP-1 agonists, HCG, and nandrolone
02 Orally disintegrating tablet (ODT) dissolves on the tongue in seconds, ideal for use during active nausea when swallowing pills is difficult
03 Does not cause sedation, extrapyramidal symptoms, or prolactin elevation, unlike dopamine-blocking anti-emetics
04 Fast onset of action (15-30 minutes oral, near-immediate for ODT) with reliable 4-8 hour duration
05 Well-tolerated with a mild side effect profile at standard doses
06 Widely available as an inexpensive generic in multiple formulations
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)
Ondansetron
Headache (most frequently reported side effect)
Constipation (5-HT3 blockade reduces gut motility)
Fatigue or dizziness
Dry mouth
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)
Known hypersensitivity to ondansetron or other 5-HT3 antagonists
Congenital long QT syndrome
Concurrent use of apomorphine (risk of severe hypotension and loss of consciousness)
Severe hepatic impairment (maximum dose should not exceed 8 mg/day)
Research Evidence
LGD-4033 Ondansetron
Status Moderate Research FDA Approved
References 5 studies 4 studies
Latest 2018 —
FDA Approved No Yes
This comparison is for educational and research purposes only. Consult a healthcare professional before use.