| Indication |
For the treatment of acid-reflux disorders (GERD), peptic ulcer
disease, H. pylori eradication, and prevention of gastroinetestinal
bleeds with NSAID use. |
| Pharmacodynamics |
Omeprazole is a compound that inhibits gastric acid secretion
and is indicated in the treatment of gastroesophageal reflux disease
(GERD), the healing of erosive esophagitis, and H. pylori
eradication to reduce the risk of duodenal ulcer recurrence. Omeprazole
belongs to a new class of antisecretory compounds, the substituted
benzimidazoles, that do not exhibit anticholinergic or H2 histamine
antagonistic properties, but that suppress gastric acid secretion by
specific inhibition of the H+/K+ ATPase at the
secretory surface of the gastric parietal cell. As a result, it inhibits
acid secretion into the gastric lumen. This effect is dose-related and
leads to inhibition of both basal and stimulated acid secretion
irrespective of the stimulus. |
| Mechanism of action |
Omeprazole is a proton pump inhibitor that suppresses gastric acid secretion by specific inhibition of the H+/K+-ATPase
in the gastric parietal cell. By acting specifically on the proton
pump, omeprazole blocks the final step in acid production, thus reducing
gastric acidity. |
| Absorption |
Absorption is rapid, absolute bioavailability (compared to intravenous administration) is about 30-40% at doses of 20-40 mg. |
| Volume of distribution |
Not Available |
| Protein binding |
95% |
| Metabolism |
Hepatic. |
| Route of elimination |
Urinary excretion is a primary route of excretion of omeprazole metabolites. |
| Half life |
0.5-1 hour |
| Clearance |
- total body cl=500-600 mL/min [healthy]
- 250 mL/min [Geriatric]
- 70 mL/min [Hepatic Impairment]
- 10 – 62 mL/min/1.73 m2 [Renal Impairment]
|
| Toxicity |
Symptoms of overdose include confusion, drowsiness, blurred
vision, tachycardia, nausea, diaphoresis, flushing, headache, and dry
mouth. |
