Effects of ibuprofen lysinate and acetylsalicylic acid on gastric and duodenal mucosa. Randomized single-blind placebo-controlled endoscopic study in healthy volunteers.

Acetylsalicylic acid (ASA, CAS 50-78-2) and ibuprofen (IB) are commonly used over-the-counter drugs for short-term treatment of pain of different origin. Ibuprofen lysinate (IBL, CAS 57469-76-8) is a water soluble form of ibuprofen for rapid absorption. This single blind, randomized, controlled study compared the incidence and severity of irritation of gastric and duodenal mucosa in normal healthy subjects (n = 45) following administration of IBL (Dolormin) 800 mg/d, ASA 2000 mg/d or placebo for 3 consecutive days. Gastric and duodenal mucosal injury were assessed endoscopically using a severity scale of 0-4 for mucosal erosions and mucosal hemorrhages. Mean gastric hemorrhage and erosion scores for ASA and IBL were significantly higher than those for placebo. In addition, ASA was found to be significantly more irritating to gastric mucosa than IBL, in both the incidence and severity of gastric erosions. No duodenal hemorrhages were detected in this study. The incidence of duodenal erosions was significantly higher in the ASA group (64%) than in both the IBL (6%) and placebo groups (0%) which were not significantly different. Only one subject (in the placebo group) reported an adverse experience (mild headache) during the study. The data suggest that both active treatments are more injurious to the gastric mucosa than placebo when given for 3 days to normal healthy volunteers, but that IBL 800 mg/d is significantly less injurious to the gastric and duodenal mucosa than ASA 2000 mg/d.