Inhibition of gastric secretion following single morning or twice daily oral administration of sufotidine to volunteers.

1. The inhibitory effect of sufotidine, a new histamine H2-receptor antagonist, on gastric secretion of acid and pepsin was studied in six healthy male volunteers. This was a three-way, cross-over, randomized, double-blind study. On each of 3 study days, the drug in a dose of 600 mg, or placebo, was administered either once or twice daily at 08.00 and 20.00 h. 2. The morning dose of sufotidine maintained intragastric pH above 3 until 18.00 h. Twice daily sufotidine maintained the pH above 3 throughout the 24 h. The median 24 h concentration of acid was significantly reduced from 86.9 mmol l-1 after placebo to 22.8 mmol l-1 and 4.9 mmol l-1 following the morning only or twice daily dose of sufotidine, respectively. Mean night-time output of acid was reduced by 81% after the morning dose of sufotidine and by 97% following treatment with sufotidine twice daily. 3. We conclude that sufotidine, in the doses studied, markedly inhibits gastric secretion and may therefore prove useful in the treatment of peptic ulceration and oesophagitis.