O-Sid

Omeprazole.

Each capsule contains Omeprazole 20 mg.

Pharmacology: Pharmacodynamics: Omeprazole is an antisecretory compound classified as substituted benzimidazole, which exhibits suppression of gastric acid secretion by specific inhibition of H⁺/K⁺/ATPase enzyme system at the secretary surface of gastric parietal cell; and has no effect on anticholinergic or histamine antagonist properties. This effect of Omeprazole is dose-related and inhibits basal and stimulated acid secretion regardless on the stimulus.
Pharmacokinetics: Omeprazole has a saturable first-pass effect that metabolized in liver by CYP450, isoenzyme CYP2C19 and CYP3A4 into inactive metabolites and excreted in urine and rarely in bile. It has high plasma protein binding which is approximately about 95% and a half-life of 0.5-3.5 hours. The duration of action is 72 hours and the onset of action is within 1 hour. While, the acid inhibitory effect lasts more than 24 hours; therefore, the administration of Omeprazole once daily is adequate. This is reversible control as when the drug is discontinued, secretary activity returns over 1-5 days.

Duodenal ulcer; Duodenal ulcer associated with H. pyroli infection; Gastric ulcer; Dyspepsia; Erosive oesophagitis; Gastro-oesophageal reflux disease (GERD); Hypersecretory condition; Zollinger-Ellison syndrome; Aspiration prophylaxis.

See Tables 1 and 2.

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* The drug should be administered at least 1 hour before meal or as directed by physicians.
* The capsule should not be chewed or broken during and before administration.
Dosage in renal impairment: Dosage adjustment does not appear necessary in patients with such impairment.
Dosage in hepatic impairment: Adjust dose to 10-20 mg once daily due to the increasing of bioavailability of the drug in hepatic impairment patients.

Administration of Omeprazole overdosage has been reported. The symptoms that temporarily occur are confusion, blurred vision, flushing, drowsiness, headache, nausea, tachycardia and dry mouth. If these symptoms have been found, the administration of appropriate fluids and electrolytes should be given along with supportive treatment because Omeprazole is extensively bound to plasma protein and is not readily dialyzable.

Hypersensitivity to any components in formulation or substituted benzimidazole is not recommended.

Atrophic gastritis has been reported in long-term treatment with Omeprazole.
The dose should be adjusted and monitored in hepatic impairment patients.
Gastric malignancy: administration of Omeprazole can suppress the symptoms and diagnosis of malignancy.
The bioavailability of the drug may be increased in elderly, different race and hepatic impairment patients.

There are no adequate controlled studies using Omeprazole in pregnant women; and it has been reported that the drug is distributed into milk. Therefore, the administration should be used during pregnancy and lactation only when the potential benefits are required.

Omeprazole is generally tolerated. The effects reported when administering the drug include: CNS effects: dizziness, asthenia, headache.
Gastrointestinal effects: abdominal pain, constipation, diarrhea, nausea, vomiting.
Other effects: back pain, cough, rash, upper respiratory tract infection, peripheral edema, agitation, insomnia, hemifacial dysesthesia, depression, pancreatitis, joint pain, thrombocytopenia and loss of taste.

As Omeprazole is metabolized by CYP450, isoenzyme CYP2C19 and CYP3A4, the use of the drug with diazepam, phenytoin, and warfarin should be concerned as it will prolong the elimination of these agents. Warfarin may have an effect on prothrombin time; the administration of the drug should be frequently monitored.
The absorption rate of dasatinib, ketoconazole, itraconazole will be decreased when administered with Omeprazole as the absorption of these agents depends on the acid and basic condition in the stomach.
The concentration of voriconazole, clarithromycin and digoxin in plasma will be increased with the concomitant use of Omeprazole and other proton pump inhibitors.
The activity of atazanavir will be decreased when administered with Omeprazole and other proton pump inhibitors.
Increasing in toxicities and adverse effects of cilostazol are reported when used with Omeprazole, the dose of cilostazol should be monitored and adjusted.
Gastric irritation effect from the use of salicylate drugs may be potentiated due to the increasing of solubility of the agent when administered with Omeprazole.
The level of Sulfonylureas in plasma will be raised, resulting in hypoglycemic phenomena. The dose should be monitored when administered with Omeprazole and other proton pump inhibitors.
Coadministration of proton pump inhibitors with sucralfate will delay the absorption and bioavailability of proton pump inhibitors.
Administration of Omeprazole and other proton pump inhibitors with benzodiazepines; for such diazepam, triazolam, may reduce the clearance, prolongs the half-life and increases the serum level of benzodiazepines. The dosage should be monitored and adjusted.

Store below 30°C, protect from light.

Antacids, Antireflux Agents & Antiulcerants

A02BC01 - omeprazole ; Belongs to the class of proton pump inhibitors. Used in the treatment of peptic ulcer and gastro-oesophageal reflux disease (GERD).

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