A case of nizatidine-induced immediate hypersensitivity

Nizatidine is a histamine H₂ receptor antagonist that inhibits stomach acid production and is commonly used in the treatment of peptic ulcer and gastroesophageal reflux. H₂ receptor antagonists are typically well tolerated, and hypersensitivity reactions are rare. A 19-year-old woman developed urticaria 30 minutes after taking a drug containing nizatidine. Allergic reactions to nizatidine were confirmed via skin prick test, which also revealed cross-reactions to ranitidine. We believe that this is the first case report on immediate hypersensitivity to nizatidine in Korea.