Gastroduodenal lesions induced by naproxen. An endoscopic evaluation of regional differences and natural course.

Gastroduodenal endoscopic findings were studied in 65 healthy volunteers receiving 750 mg or 1000 mg naproxen for 1 or 2 weeks. Separate registration of the mid- and distal duodenum showed that mucosal toxicity can be demonstrated even distally to the duodenal bulb. The lesions were closely correlated to the findings in the stomach and duodenal bulb, though generally somewhat less extensive. Whereas a difference between 750 mg and 1000 mg naproxen was demonstrated in an intraindividual comparison (n = 26; median sum of visual analogue scale score in the stomach/duodenal bulb, 129 mm and 183 mm, respectively; p less than 0.05), no difference was seen in two parallel groups (n = 32 and 33). In the stomach and duodenal bulb, a significant aggravation of mucosal lesions was seen from 1 to 2 weeks in 16 subjects. Healing was complete in 10/12 subjects after 3 weeks, independent of the extent of the initial damage.