Best NAC for Liver
Top 6 products ranked
Last reviewed May 2026
Clinical dose: 600–1800 mg
Why NAC for Liver
NAC plays a key role in liver. NAC is a precursor to glutathione, the body's primary intracellular antioxidant. Supports liver detoxification, respiratory health, and cellular defense against oxidative stress. In clinical studies, nac supports liver detoxification and cellular protection.
What dose to look for
Clinical studies typically use 600–1800 mg of nac. Most studies use 600–1200 mg/day. Higher doses (up to 1800 mg) used in some clinical contexts. Often taken in divided doses. Products below this range may not deliver meaningful results.
What the research says
NAC has moderate clinical evidence for liver benefits. Precursor to glutathione with established medical use for acetaminophen toxicity and mucolytic therapy Learn more
Clinical research on NAC (N-Acetylcysteine)
HIGH — Standard of care for acetaminophen toxicity, multiple liver RCTs · 600–1,800 mg/day (oral supplementation); 150 mg/kg IV loading dose (emergency)
- •NAC is the standard of care for acetaminophen (paracetamol) overdose worldwide. The Prescott protocol (1979) established IV NAC as life-saving treatment, reducing hepatotoxicity mortality from ~5% to <0.5% when administered within 8 hours. PubMed
- •2009 RCT (173 patients with non-acetaminophen acute liver failure) found IV NAC improved transplant-free survival in early-stage hepatic encephalopathy (52% vs 30%), establishing benefit beyond acetaminophen toxicity. PubMed
- •2021 meta-analysis of 5 RCTs found NAC supplementation significantly reduced ALT levels in NAFLD patients. Effects were modest but consistent across trials. PubMed
- •Mechanism: NAC is a precursor to glutathione, the liver's primary endogenous antioxidant. Replenishes hepatic glutathione stores depleted by oxidative stress, alcohol, and drug metabolism.
- •Important nuance: emergency IV NAC dosing is vastly different from oral supplementation. Oral bioavailability is only 6–10%. Supplement doses (600–1,800 mg/day) support glutathione synthesis but should not be conflated with the acute toxicity protocol.
