Early effects of lafutidine or rabeprazole on intragastric acidity: which drug is more suitable for on-demand use?
BACKGROUND
Medication for the relief of heartburn should have the rapid onset of action required for on-demand use. We studied the inhibition of gastric acid secretion by lafutidine and rabeprazole, given in single doses to fasting and postprandial subjects.


METHODS
A total of 22 healthy male, Helicobacter pylori-negative volunteers participated in this randomized, two-way crossover study. They were randomly assigned to receive a single oral dose of 10 mg lafutidine or 20 mg rabeprazole after fasting overnight (12 subjects, fasting study) or after eating a test meal (noodles, 364 kcal; protein, 10.1 g; fat, 16 g; carbohydrates, 44.9 g; NaCl, 1.1 g; 10 subjects, postprandial study). Intragastric pH was monitored continuously for 6 h after treatment. The other drug was given after a washout period of at least 7 days, and intragastric pH was similarly monitored.


RESULTS
In the fasting study, lafutidine sustained pH at >3 and >4 during the second, third, fourth, fifth, and sixth hours of the study for significantly longer than rabeprazole. During the first 6 h after treatment, lafutidine sustained pH at more than 2, 3, 3.5, 4, 5, 6, and 7 longer than rabeprazole. In the postprandial study, lafutidine sustained pH >3 and >4 for longer periods than rabeprazole during the third, fourth, fifth, and sixth hours of the study. During the first 6 h after treatment, lafutidine sustained pH at more than 2, 3, 3.5, 4, 5, 6, and 7 longer than rabeprazole.


CONCLUSIONS
Lafutidine 10 mg produces a prompter rise in intragastric pH than rabeprazole 20 mg in fasting and postprandial Helicobacter pylori-negative male subjects.
Inamori
Masahiko
M
Gastroenterology Division, Yokohama City University School of Medicine, 3-9 Fukuura, Kanazawa-ku, Yokohama, 236-0004, Japan.
Togawa
Jun-Ichi
J
Iwasaki
Tomoyuki
T
Ozawa
Yutaka
Y
Kikuchi
Taisuke
T
Muramatsu
Kenichi
K
Chiguchi
Gaku
G
Matsumoto
Shuhei
S
Kawamura
Harunobu
H
Abe
Yasunobu
Y
Kirikoshi
Hiroyuki
H
Kobayashi
Noritoshi
N
Shimamura
Takeshi
T
Kubota
Kensuke
K
Sakaguchi
Takashi
T
Saito
Satoru
S
Ueno
Norio
N
Nakajima
Atsushi
A
D053799:2-Pyridinylmethylsulfinylbenzimidazoles; D000081:Acetamides / Q000008:administration & dosage*; D000284:Administration, Oral; D000328:Adult; D001562:Benzimidazoles / Q000008:administration & dosage*; D018592:Cross-Over Studies; D004334:Drug Administration Schedule; D005744:Gastric Acid / Q000378:metabolism; D005745:Gastric Acidity Determination; D006356:Heartburn / Q000175:diagnosis / Q000188:drug therapy*; D006801:Humans; D006863:Hydrogen-Ion Concentration; D008297:Male; D008991:Monitoring, Physiologic; D009853:Omeprazole / Q000008:administration & dosage / Q000031:analogs & derivatives*; D010880:Piperidines / Q000008:administration & dosage*; D019518:Postprandial Period / Q000187:drug effects*; D011725:Pyridines / Q000008:administration & dosage*; D064750:Rabeprazole; D012016:Reference Values; D018570:Risk Assessment; D013997:Time Factors; D016896:Treatment Outcome
D053799:2-Pyridinylmethylsulfinylbenzimidazoles; D000081:Acetamides; D001562:Benzimidazoles; D010880:Piperidines; D011725:Pyridines; D064750:Rabeprazole; C076948:lafutidine; D009853:Omeprazole