Description
RABEPRAZOLE
Rabeprazole is a PPI that suppresses gastric acid secretion by inhibiting the gastric H+/K+ ATPase at the secretory surface of the gastric parietal cell.
ITOPRIDE
Itopride increases acetylcholine (ACh) concentrations by inhibiting dopamine D2 receptors and acetyl cholinesterase. Higher ACh increases GI peristalsis, increases the lower esophageal sphincter pressure, stimulates gastric motility, accelerates gastric emptying, and improves gastro-duodenal coordination.
PHARMACOLOGY
1.RABEPRAZOLE
Pharmacodynamics: – Rabeprazole sodium is a proton pump inhibitor. It is a prodrug. After administration it diffuses in to the parietal cell of the stomach and accumulates in the secretory canaliculi. In the acidic medium Rabeprazole is converted to sulfenamide. This sulfenamide covalently interacts with sulfhydryl (SH) group in the proton pump (H+ K+ATPase) and inhibits the exchange of extracellular K+ for intracellular H+ ion. Rabeprazole sodium irreversibly inhibits proton pumps activity and decreases gastric acid secretion. Rabeprazole produces fastest acid suppression and helps in mucin synthesis.
2.ITOPRIDE
Itopride has three way actions. It inhibits the dopamine D2 receptor at the parasympathetic nerve ends. It increases the release of acetylcholine and decreases the metabolism of acetylcholine by inhibiting the enzyme acetyl cholinesterase (AChE). By maintaining higher acetylcholine levels, itopride increases the esophageal and gastrointestinal peristalsis, increases the lower esophageal sphincter pressure, stimulates gastric motility, accelerates gastric emptying and improves gastro-duodenal coordination. Itopride exerts anti-emetic actions because of its dopamine D2 receptor antagonistic action at CTZ.
PHARMACOKINETICS:
1. RABEPRAZOLE:
Absorption: Rabeprazole sodium is well absorbed after oral administration and its bioavailability is about 50% since it undergoes first pass metabolism.
Distribution: It is widely distributed in the body in protein bound form.
Metabolism: Rabeprazole sodium is extensively metabolised in the liver.
Excretion: It is excreted mainly in the urine and small amount in feces.
2. ITOPRIDE:
Absorption: it is orally well absorbed after oral administration.
Metabolism: Itopride undergoes extensive hepatic metabolism.
INDICATIONS:
Peptic ulcer, erosive and ulcerative GERD (Gastroesophageal reflux disease).
treatment of pathological hypersecretory conditions (Zollinger- Ellison syndrome),
Helicobacter pylori eradication to reduce the risk of duodenal ulcer recurrence
