<prompt> The oral fatal dose of potassium cyanide is5-10 mg1-2 mg200-300 mg1-2 gm  <response>: Fatal dose: 50 to 60 mg of pure acid 200-300mg of NaCN and KCN Fatal period: HCN 2-10 min NaCN and KCN 30 min Ref: FORENSIC MEDICINE AND TOXICOLOGY Dr PC IGNATIUS THIRD EDITION PAGE 472 