Symptoms: severe pain in the oral cavity, along the esophagus, in the abdomen, vomiting, diarrhea; the oral and pharyngeal mucosa is edematic, dark brown, purple, laryngeal edema, mechanical asphyxia, burn shock, motor excitement, seizures, parkinsonism, hemorrhagic colitis, nephropathy, hepatopathy. With reduced acidity of gastric juice, it is possible to developMethemoglobinemia with pronounced cyanosis and dyspnea. The lethal dose for children is about 3 g, for adults - 0.3 - 0.5 g / kg.
Treatment: methylene blue (50 ml 1 % solution), ascorbic acid (in / in - 30 ml of a 5% solution), cyanocobalamin - up to 1 mg, pyridoxine (in / m - 3 ml of 5% solution).