Single Morning and Nightly Doses of Ranitidine 300 mg: An Appraisal of Their Antisecretory Effects by Continuous pH Monitoring

Abstract

Gastric acidity of 12 patients with healed duodenal ulcers was continuously monitored over 24 h in order to assess the antisecretory effects of two different administration times of a single daily dose of ranitidine 300 mg. Each patient orally received either (a) placebo at 08.00 h and 22.00 h; (b) ranitidine 300 mg at 08.00 h and placebo at 22.00 h, or (c) placebo at 08.00 h and ranitidine 300 mg at 22.00 h in randomized and double-blind fashion. Each medication was administered on three separate occasions, with intervals of at least 1 week. Both the morning and the bedtime doses of ranitidine were significantly superior (p < 0.001) to placebo in controlling 24-hour gastric acidity, while, in the same period, ranitidine nocte was more effective (p < 0.001) than ranitidine mane. During the night, bedtime ranitidine caused more acid inhibition (p < 0.001) than morning ranitidine, but the opposite (p < 0.01) occurred during the daytime. This study shows that the antisecretory effect of morning ranitidine during the daytime is less consistent than that achieved by bedtime ranitidine during the nocturnal period. As similar rates of duodenal ulcer healing have recently been achieved with morning and conventional nighttime administration of H₂ antagonists, it becomes clear that antisecretory drugs can also be beneficial with an acid inhibition which is shorter-lasting than that which was previously thought to be necessary or, alternatively, that also daytime acidity is important in ulcerogenesis.

Circadian rhythms and medical diseases: Does it matter when drugs are taken?

“…Ranitine, given during night-time, was associated with a higher inhibition of intragastric acidity either in healthy subjects [80], and in patients with duodenal ulcer with nocturnal acid breakthrough [81].…”

Pharmacodynamic Aspects of Modes of Drug Administration for Optimization of Drug Therapy

“…Following this, a single daily night regimen of H 2 -receptor antagonists was shown to produce better control of gastric pH compared to once-a-day morning administration. 92,93 This is because the intragastric contents are buffered by food during the day, leading to lower apparent antisecretory effect following morning drug administration.…”

Acid Inhibitory Characteristics of Nizatidine in Man: An Overview

“…Recent clinical studies have shown that large, single, morning doses of H2-antagonists are as effective as equivalent single nocturnal doses in promoting healing of DUs (22,23), although morning administration has a shorterlasting action than bedtime dosing (22, 24). This apparent discrepancy may be explained by the fact than inhibition of diurnal acidity may be more important than the inhibition of nocturnal acidity, provided that the period of reduced acidity obtained is long enough to allow the healing process to take place.…”