Hogan D L, McQuaid K R, Koss M A, Crombie D L, Hunter S, Metz C, Euler A R, Isenberg J I
Division of Gastroenterology, University of California San Diego.
Aliment Pharmacol Ther. 1993 Oct;7(5):537-41. doi: 10.1111/j.1365-2036.1993.tb00130.x.
It has been proposed that famotidine may be effective in maintaining intragastric pH > or = 4 for up to 12 h with a single i.v. 20 mg bolus injection and thereby prevent acute stress-related mucosal haemorrhage. The present study was designed to compare a ranitidine continuous i.v. infusion (6.25 mg/h) vs. famotidine bolus injection (20 mg every 12 h) on 24-h intragastric pH and gastric acid secretion. Twenty-eight healthy volunteers (15 males, 13 females; 20-56 years) participated in two 24-h treatment periods; each test was in random order separated by 7-10 days. After an overnight fast, subjects were intubated and gastric pH and acid secretion measured hourly. Whereas ranitidine maintained gastric pH above 4 for the entire 24-h period, mean pH steadily decreased to a nadir of 2.9 and 3.7, respectively, 12 h after each famotidine injection (P < 0.01 vs. ranitidine). Furthermore, gastric acid secretion increased to 4.4 +/- 1.2 mmol/h 12 h after famotidine injection compared to 1.1 +/- 0.3 mmol/h with ranitidine (P < 0.01). We conclude that ranitidine delivered as a continuous i.v. infusion (6.25 mg/h) is superior to bolus famotidine injections (20 mg) at 12-h intervals in suppressing gastric acid secretion and maintaining an intragastric pH > or = 4. More frequent famotidine dosing, or delivery by continuous i.v. infusion, may be required to provide prolonged acid suppression.
有人提出，法莫替丁单次静脉推注20mg可能有效维持胃内pH值≥4长达12小时，从而预防急性应激相关黏膜出血。本研究旨在比较雷尼替丁持续静脉输注（6.25mg/h）与法莫替丁推注（每12小时20mg）对24小时胃内pH值和胃酸分泌的影响。28名健康志愿者（15名男性，13名女性；20 - 56岁）参与了两个24小时治疗期；每次测试按随机顺序进行，间隔7 - 10天。经过一夜禁食后，受试者插管，每小时测量胃pH值和胃酸分泌。雷尼替丁在整个24小时期间维持胃pH值高于4，而每次法莫替丁注射后12小时，平均pH值分别稳步下降至最低点2.9和3.7（与雷尼替丁相比，P < 0.01）。此外，法莫替丁注射后12小时胃酸分泌增加至4.4±1.2mmol/h，而雷尼替丁为1.1±0.3mmol/h（P < 0.01）。我们得出结论，在抑制胃酸分泌和维持胃内pH值≥4方面，持续静脉输注（6.25mg/h）的雷尼替丁优于每12小时一次的法莫替丁推注（20mg）。可能需要更频繁地给药或持续静脉输注法莫替丁，以提供更长时间的胃酸抑制。
