Pharmacodynamic effects of single doses of rabeprazole 20 mg and pantoprazole 40 mg in patients with GERD and nocturnal heartburn.
BACKGROUND
Rabeprazole and pantoprazole are both used for symptomatic treatment of gastro-oesophageal reflux disease (GERD). Speed and duration of acid suppression and intensity of effect after a single dose may be important pharmacodynamic properties in clinical use.


OBJECTIVE
To compare antisecretory effects of single doses of rabeprazole and pantoprazole in patients with GERD and a history of nocturnal heartburn.


METHODS
An open-label, randomized, two-way crossover, clinical pharmacology study was conducted. Twenty-nine Helicobacter pylori-negative GERD patients (17 men, mean age 44 years), with a history of nocturnal heartburn (mean frequency 4.7 episodes/week), received a single dose of rabeprazole 20 mg or pantoprazole 40 mg, with a 14-day 'washout'. Intragastric pH was recorded continuously from 24 h before to 24 h after dosing.


RESULTS
Mean area under the intragastric pH-time curve (AUC) was significantly higher after dosing with rabeprazole 20 mg than with pantoprazole 40 mg in all time intervals analysed, including night (P </= 0.02). Mean percentage time with pH > 3 and >4 was significantly greater after rabeprazole than pantoprazole in all time intervals (P </= 0.004).


CONCLUSIONS
In GERD patients with nocturnal heartburn, a single oral dose of rabeprazole 20 mg increased intragastric pH more than pantoprazole 40 mg did throughout the 24 h after dosing.
Warrington
S
S
Hammersmith Medicines Research Ltd, Central Middlesex Hospital, London, UK. swarrington@hmrlondon.com
Baisley
K
K
Lee
D
D
Lomax
K
K
Delemos
B
B
Boyce
M
M
Morocutti
A
A
D053799:2-Pyridinylmethylsulfinylbenzimidazoles / Q000008:administration & dosage / Q000494:pharmacology*; D000293:Adolescent; D000328:Adult; D000368:Aged; D000897:Anti-Ulcer Agents / Q000008:administration & dosage / Q000493:pharmacokinetics*; D018592:Cross-Over Studies; D005260:Female; D005744:Gastric Acid / Q000378:metabolism*; D005745:Gastric Acidity Determination; D005764:Gastroesophageal Reflux / Q000188:drug therapy*; D006356:Heartburn / Q000188:drug therapy*; D006801:Humans; D006863:Hydrogen-Ion Concentration / Q000187:drug effects; D008297:Male; D008875:Middle Aged; D000077402:Pantoprazole; D064750:Rabeprazole
D053799:2-Pyridinylmethylsulfinylbenzimidazoles; D000897:Anti-Ulcer Agents; D064750:Rabeprazole; D000077402:Pantoprazole