Pill-induced esophageal strictures: clinical features and risk factors for development.

Clinical data from five subjects with pill-induced esophageal strictures and from the English-language literature on pill-induced esophageal damage were reviewed to determine risk factors for stricture development and to characterize this complication. Including our five cases, 195 patients with pill-induced damage and 39 patients with pill-induced strictures have been reported to date. Seventy-eight percent of the strictures were located in the proximal or mid-esophagus. Potassium chloride or quinidine preparations were incriminated in 60% of cases and were more likely to produce stricture than other medications commonly associated with esophageal damage (e.g., tetracycline). Older age, male gender, left atrial enlargement, ingestion of sustained-release formulations, and prior esophageal structural abnormality were all more commonly present in the subset with strictures (p less than 0.05 for each), even after appropriately controlling for medication. A logistic regression analysis revealed that older age and ingestion of sustained-release formulations were the most significant independent factors associated with stricture development (p less than 0.0001 for each). These findings indicate that stricture formation from pill-induced esophageal damage is dependent upon host-related factors as well as the caustic nature of the pill.