Hepatotoxicity

Hepatotoxicity describes hepatocyte injury or cholestatic dysfunction caused by a xenobiotic. In AAS pharmacology the concern concentrates on 17α-alkylated orals — the substitution enabling oral bioavailability (by blocking glucuronidation at 17β) forces the liver onto a glutathione-demanding detoxification route.

Biomarker interpretation — the standard panel misleads without context:

– ALT (alanine aminotransferase): hepatocyte-specific. Values >2× upper-reference-limit warrant dose review. >3× demand cessation.
– AST (aspartate aminotransferase): not hepatocyte-specific. Elevated AST with normal ALT and elevated CK points to skeletal muscle, not liver — a standard pattern in heavy lifters mid-block, often misread as drug toxicity.
– GGT (gamma-glutamyl transferase): the clean signal for alkylated-oral hepatotoxicity. Rises before ALT on stanozolol and methandrostenolone.
– ALP (alkaline phosphatase): elevated in cholestatic injury. Paired GGT elevation confirms hepatic origin.
– Direct bilirubin: the functional readout. Rising above 0.3 mg/dL signals clinical cholestasis, irrespective of transaminase values.

Hepatotoxicity graded by mechanism and dose-range:

– Oxymetholone (Anadrol): severe. Documented case reports of cholestatic jaundice at 50 mg/day for 6+ weeks. Peliosis hepatis risk at long-term use.
– Methyltestosterone: severe. Historical data is extensive — the compound that established the alkylated-oral hepatotoxicity class.
– Methandrostenolone (Dianabol): moderate. Transaminase elevation at 30 mg/day is the expected finding; normalises within 4 weeks of cessation in the absence of co-hepatotoxic exposure.
– Stanozolol (Winstrol): moderate-high. Cholestatic pattern with elevated GGT and bilirubin is characteristic.
– Oxandrolone (Anavar): mild. The 2-oxa substitution in the A-ring reduces hepatic burden relative to the class — it does not eliminate it.

Non-hepatotoxic despite folklore:

Injectable testosterone esters at clinical dose, nandrolone, boldenone, trenbolone. Most peptides. Most SARMs, with exceptions — MK-677 is non-hepatotoxic, MK-2866 has limited human data, RAD-140 showed documented transaminase elevations in phase I oncology trials.

Hepatoprotective protocols — separating evidence from marketing:

– TUDCA 500 mg/day: mechanism is bile-acid pool displacement, pushing endogenous cholate and chenodeoxycholate into secretion. Clinical-trial evidence is solid in cholestatic disease; AAS-specific data is anecdotal but mechanistically plausible.
– NAC 600–1200 mg/day: glutathione precursor. Replenishes the cofactor the liver consumes processing alkylated compounds. Direct evidence in acetaminophen toxicity; extrapolated to AAS.
– Milk thistle (silymarin): weak data. Poor oral bioavailability; in vitro antioxidant activity does not reliably translate to in vivo hepatoprotection.
– Alcohol avoidance is not optional. Ethanol is a direct hepatotoxin via CYP2E1; co-exposure with alkylated orals is synergistic, not additive.

Referred pain from hepatomegaly on oxymetholone is not a sign that the hepatoprotectant is working. It is organ stress. The correct response is cessation, not reassurance.