Local cauterizing effect. When ingested - burns of the mucous membrane of the gastrointestinal tract, exotoxic burn shock, repeated esophageal-gastric bleeding, mechanical asphyxia as a result of burns and laryngeal edema. Burn disease, reactive peritonitis.
At a later stage (at 3-4 weeks), a cicatricial narrowing of the esophagus develops, and rarely, of the antrum of the stomach. Main complications: late ulcer bleeding, aspiration pneumonia. Treatment - see Strong acids.