This article presents an experimental method using cats for investigation of the local ulcerogenic properties of oral drugs in the esophagus. 15 drugs in current clinical use were tested. The drugs were placed in esophagus and the animals were sacrificed after 5–8 h, 4–7 or 21 days. The esophagus was cut open, photographed macroscopically and sectioned for light microscopy. Several drugs, e.g. doxycycline, alprenolol, propranolol, ferrosuccinate, ferrosulfate, and emepronium bromide showed marked ulcerogenic properties, whereas indomethacin and betamethasone did not cause any lesions in the cat esophagus. The results seem to be in accordance with the local effect these same drugs exert on the human esophageal mucosa. In order to predict and prevent drug-induced esophageal lesions in man we suggest that oral drugs should be tested concerning their local ulcerogenic properties in the esophagus.

Medication with oral drugs has not been considered as a cause of esophageal lesions in the general literature of esophageal disease. This study demonstrates 40 patients with complaints of sudden onset of intense retrosternal pains and odynophagia during treatment with oral tetracyclines. All patients had distinct circumferential ulcers in the esophagus. Medical history, barium swallows, esophagoscopy, biopsies and esophageal manometry revealed no other apparent etiology but a local corrosive effect of the tetracyclines. Experimental tests on the esophagus of the cat verified a severe local corrosive effect of the tetracyclines. Another tetracycline, lymecycline, not reported previously to induce esophageal lesions in man, was significantly less ulcerogenic than doxycycline and oxytetracycline. Drug induced esophageal ulcerations are likely to be more numerous than previously suspected. The experimental model used appears to be sound for investigating ulcerogenic potentials of orally administered drugs.