Miner P B, Allgood L D, Grender J M
Oklahoma Foundation for Digestive Research, University of Oklahoma Health Sciences Center, Oklahoma City, OK 73104, USA.
Aliment Pharmacol Ther. 2007 Jan 1;25(1):103-9. doi: 10.1111/j.1365-2036.2006.03129.x.
The onset of acid inhibition for proton pump inhibitors is slower than with H2RAs and generally considered to be at a steady-state after 5 days. Thus, little direct comparison data exists between H2RAs and proton pump inhibitors for gastric acid suppression on day 1 of therapy. Furthermore, the durability of their acid suppression has not been systematically compared.
To compare the effects of 20.6 mg omeprazole magnesium o.m. (Ome-Mg 20), famotidine 10 mg b.d. (Fam 10) and famotidine 20 mg b.d. (Fam 20) on intragastric pH on day 1 and throughout 14 days of dosing.
The study was a randomized, double-blind, three-dosing regimens, three-period crossover. Healthy adults with frequent heartburn (> or =2 days/week) underwent 24-h gastric pH monitoring on days 0 (baseline), 1, 3, 7 and 14.
Thirty-one subjects were included in the per-protocol analyses. On day 1, the mean percentage time pH > 4 (pH4%) was higher for Ome-Mg 20, 44.6%, than for Fam 10, 36.7% (P = 0.032), and not different from Fam 20, 46.9% (P = 0.541). The pH4% was higher for Ome-Mg 20 than either famotidine regimen on all subsequent monitoring days (P < 0.001). The 24-h area under the mean intragastric pH curve showed a similar pattern. Furthermore, after day 1, Ome-Mg 20 demonstrated an increasing and sustained effect in contrast to a decreasing effect for famotidine, consistent with H2RA tolerance.
Gastric acid suppression on Ome-Mg 20 mg o.m. over 14 days was comparable with Fam 10 mg b.d. or Fam 20 mg b.d. on day 1, and superior thereafter.
质子泵抑制剂的抑酸起效速度比H2受体拮抗剂慢，一般认为5天后达到稳态。因此，在治疗第1天，H2受体拮抗剂和质子泵抑制剂之间关于胃酸抑制的直接比较数据很少。此外，它们的抑酸持久性尚未得到系统比较。
比较20.6毫克奥美拉唑镁口服（Ome-Mg 20）、法莫替丁10毫克每日两次（Fam 10）和法莫替丁20毫克每日两次（Fam 20）在给药第1天及整个14天给药期间对胃内pH值的影响。
该研究为随机、双盲、三种给药方案、三期交叉试验。有频繁烧心症状（≥每周2天）的健康成年人在第0天（基线）、第1天、第3天、第7天和第14天接受24小时胃pH值监测。
符合方案分析纳入了31名受试者。在第1天，Ome-Mg 20的pH>4的平均时间百分比（pH4%）为44.6%，高于Fam 10的36.7%（P = 0.032），与Fam 20的46.9%无差异（P = 0.541）。在所有后续监测日，Ome-Mg 20的pH4%均高于两种法莫替丁给药方案（P < 0.001）。平均胃内pH曲线下的24小时面积呈现类似模式。此外，在第1天后，Ome-Mg 20表现出持续增强的效果，而法莫替丁则呈现下降效果，这与H2受体拮抗剂的耐受性一致。
14天内服用20毫克奥美拉唑镁口服，在第1天对胃酸的抑制作用与每日两次服用10毫克法莫替丁或每日两次服用20毫克法莫替丁相当，此后则更优。
