LGD-4033 (Ligandrol)

Structure: Non-steroidal SARM. High binding affinity for androgen receptors. More potent than ostarine on a per-milligram basis, with correspondingly greater suppression and hepatotoxicity risk.

Dosage:

• Bodybuilding: 5-20 mg/day for 8-12 weeks
• Phase I clinical dose (Basaria et al., 2013): 0.1-1 mg/day
• Conservative starting dose: 5 mg/day

Administration:

• Oral. No injection required.
• Available as raw powder, liquid suspension, or capsule (research-chemical grade only; no approved pharmaceutical).
• Once-daily dosing. Morning preferred.

Key Notes:

• Basaria et al. (2013) Phase I trial: dose-dependent suppression of total testosterone, SHBG, and HDL at doses as low as 0.1-1 mg/day in healthy young men. Lean mass increased dose-dependently but so did suppression.
• Highest DILI risk of any SARM: multiple published case reports of cholestatic jaundice. Barbara et al. (2020) reported cholestatic jaundice after 2 weeks at 10 mg/day (bilirubin, ALP, GGT all markedly elevated; resolved on cessation).
• Liver function tests (ALT, AST, ALP, GGT, bilirubin) should be checked at baseline, mid-cycle, and post-cycle. Discontinue immediately if cholestatic pattern emerges.
• HPTA suppression is moderate to severe; a SERM-based PCT is recommended after any cycle. Testosterone, LH, and FSH may take 4-12 weeks to recover.
• HDL suppression is consistent and clinically meaningful at bodybuilding doses.
• Does not aromatise; estradiol is typically suppressed (low-E2 symptoms possible).
• WADA prohibited under S1 (anabolic agents). Detection window of approximately 22 days in urine.
• All commercially available product is research-chemical grade with no regulatory oversight for purity or dose accuracy.