The invention is for the combination and related methods of N-acetyl-cysteine oral, inhaled, or intravenous, or glutathione inhaled or intravenous, generally in combination with antibiotic and / or antiviral therapy to ameliorate the toxic effects of infection with materials used in Bioterror incidents such as Bacillus anthracis and smallpox virus, and alternatively, upon exposure to radiation, during testing, and vaccination, as treatment prior to treatment with antibiotic or antiviral therapy to ameliorate the toxic effects of infection and exposure with these organisms.