[The action of various doses of the new imidazole H2-receptor antagonist etintidine on intragastric acidity in man].

The chemical structure of etintidine differs from that of cimetidine by the addition of an ethinyl group to the terminal methyl group of the side chain. We investigated the influence of etintidine 300 or 400 mg b.d. and of etintidine 300 or 600 mg nocte, cimetidine 800 mg nocte versus placebo in two different double-blind randomized cross-over studies on 24-h intragastric acidity and nocturnal volume and acid secretion (12:00 midnight to 6:00 a.m.) in 12 and 8 healthy male volunteers, respectively. 5-10 ml of gastric contents were aspirated hourly via a nasogastric tube. The pH of the samples was determined using a glass electrode. The results were expressed in terms of H+-activity (mmol/l). Etintidine 300 or 400 mg b.d. reduced day- and nighttime acidity by 53 and 60% or 41 and 41%, respectively. Nocturnal acid secretion (mmol/l) was inhibited by 38 and 42%, resp. Etintidine 300 or 600 mg nocte and cimetidine 800 mg nocte (9:00 p.m.) lowered nocturnal intragastric acidity by 69, 84 and 79%, resp. Daytime inhibition was not observed. Our results suggest, that 1. etintidine 300 and 400 mg b.d. are equipotent in promoting peptic ulcer healing and 2. that this new imidazole H2-receptor antagonist is also effective in a single bedtime dose.