Mucoprotec Mechanism of Action

Peptic Ulcer and Gastro-oesophageal Reflux Disease.
Pharmacology: Pharmacokinetics: Rebamipide improves the speed and quality of peptic ulcer healing whether given alone or in combination with proton pump inhibitors or H₂ receptor antagonists and has been shown to reduce the rate of recurrence of gastric ulcers, regardless of the status of Helicobacter pylori infection. The ability of rebamipide to effect healing of acute gastritis and gastric ulcers is presumed to be due to its gastric cytoprotective action which results from its ability to increase gastric mucosal endogenous prostaglandin production and to scavenge hydroxyl radicals. Rebamipide has also been shown to be as effective as misoprostol in preventing nonsteroidal anti-inflammatory drug (NSAID)-induced gastric mucosal injury perhaps by preventing the decrease in gastric mucosal blood flow seen in patients taking NSAIDs. In addition, studies done in animals and human subjects indicate that one of the principal gastric defense mechanisms afforded by Rebamipide is through an increased gastric mucus secretion, probably resulting from the stimulation of endogenous prostaglandin production in the gastric mucosa. Futhermore, Rebamipide suppresses gastric mucosal inflammation which is thought to be related to inhibition of superoxide anion production from neutrophils, scavenging of hydroxyl radicals and inhibition of interleukin 8 production.
Rebamipide administered orally as 100 mg tablets reaches peak plasma concentrations (T_max) in 2.4 hours and has an elimination half-life (T_½) of 1.94 hours. Oral administration of Rebamipide after a meal delayed its absorption but did not have any effect on its bioavailability. Rebamipide is highly protein bound with plasma protein binding of around 98%. Rebamipide is excreted mainly as the unchanged drug in the urine after oral administration. Administration of single doses of Rebamipide 100 mg tablets in patients with renal insufficiency resulted in higher plasma concentrations and longer elimination half-lives compared to normal healthy subjects. Repeated oral administrations of Rebamipide in steady-state conditions among renal failure patients undergoing dialysis resulted in plasma concentrations that were almost similar to that observed with single oral administrations indicating that the drug does not accumulate.