The standard dose of milk thistle is based on its silymarin content, 70 to 210mg three times daily. For this reason, standardized extracts, typically 80% silymarin content, are preferred.
NAC (N-Acetyl L-Cysteine) Daily dose: 500 to 800 mg per day (less in people with elevated mercury levels, from dental amalgams and ingestion of mercury-containing seafood).