title: Effect of different doses of omeprazole on 24-hour oesophageal acid exposure in patients with gastro-oesophageal reflux.
abstract: To define the optimum doses of omeprazole appropriate for acute and long-term therapy of patients with gastro-oesophageal reflux disease, 24-h oesophageal pH was measured in 12 patients with symptomatic reflux and an abnormal 24-h oesophageal acid exposure time (greater than 6%) in a randomized, double-blind, four-way crossover study comparing the effects of omeprazole 10, 20, or 40 mg/day and placebo. Total reflux time over 24 hours, number of reflux episodes per hour, and the number of reflux episodes lasting greater than 5 minutes were measured by ambulatory 24-h oesophageal pH monitoring. All doses of omeprazole were superior to placebo in decreasing gastro-oesophageal reflux as measured by each index. With placebo, oesophageal acid exposure was 16.3% of the 24 hours, 10 mg omeprazole/day reduced that to 6.3%, 20 mg/day lowered acid exposure to 0.9%, and 40 mg/day to 0.6%. Thus only the 20 and 40 mg doses reduced acid exposure to within the normal range. Similar results were obtained with the other indices of reflux. These data suggest that a rational dose regimen for reflux oesophagitis is 20 mg/day, a regimen that has proved effective in clinical trials. The present study indicates that 24-hour oesophageal pH monitoring is a practical approach to the determination of drug dosage in patients with gastro-oesophageal reflux.
authors.affiliation: Oklahoma Foundation for Digestive Research, Oklahoma City 73104.
authors.forename: M
authors.initials: M
authors.lastname: Robinson
authors.forename: P N
authors.initials: PN
authors.lastname: Maton
authors.forename: M L
authors.initials: ML
authors.lastname: Allen
authors.forename: T J
authors.initials: TJ
authors.lastname: Humphries
authors.forename: D
authors.initials: D
authors.lastname: McIntosh
authors.forename: A J
authors.initials: AJ
authors.lastname: Cagliola
authors.forename: T E
authors.initials: TE
authors.lastname: Bradstreet
mesh_terms: D000328:Adult; D000368:Aged; D004305:Dose-Response Relationship, Drug; D004311:Double-Blind Method; D004947:Esophagus / Q000187:drug effects* / Q000502:physiology; D005260:Female; D005764:Gastroesophageal Reflux / Q000188:drug therapy*; D006356:Heartburn / Q000188:drug therapy; D006801:Humans; D006863:Hydrogen-Ion Concentration; D008297:Male; D008875:Middle Aged; D009853:Omeprazole / Q000009:adverse effects / Q000627:therapeutic use*; D013997:Time Factors
chemical_list: D009853:Omeprazole