Omez 10

Omeprazole 10 mg.

Pharmacology
Mechanism of Action
PPI; binds to H+/K+-exchanging ATPase (proton pump) in gastric parietal cells, resulting in suppression of basal and stimulated acid secretion

Absorption
Bioavailability: 30-40%
Onset of action: 1 hr (antisecretory effect)
Duration: 73 hr
Peak plasma time: 0.5-3.5 hr
Peak response (PUD): 2 hr (initial); 5 days (peak)

Distribution
Protein bound: 95-96%
Vd: 0.39 L/kg

Metabolism
Metabolized extensively by hepatic CYP2C19; slow metabolizers are deficient in CYP2C19 enzyme system; plasma concentration can increase by 5-fold or higher in comparison with that found in persons with the enzyme
Metabolites: Hydroxyomeprazole, omeprazole sulfone, omeprazole sulfide (inactive)
Enzymes inhibited: CYP2C19

Elimination
Half-life: 0.5-1 hr; increases to 3 hr with hepatic impairment
Dialyzable: No
Total body clearance: 500-600 mL/min
Excretion: Urine (77%); feces (16-19%; mainly in bile)

Pharmacogenomics
CYP2C19 poor metabolizers

  • Asians have ~4-fold higher exposure to omeprazole than whites
  • CYP2C19, a polymorphic enzyme, is involved in the metabolism of omeprazole
  • ~15-20% of Asians are CYP2C19 poor metabolizers
  • Tests are available to identify a patient’s CYP2C19 genotype
  • Avoid use in Asian patients with unknown CYP2C19 genotype or those who are known to be poor metabolizers

Remember, keep this and all other medicines out of the reach of children, never share your medicines with others, and use Omez 10 only for the indication prescribed.