Higher AUCs on oral administration of omeprazole and felodipine in Indian volunteers--are they clinically important?
Bioavailability studies with single oral doses of omeprazole 20 mg (enteric coated formulation) and felodipine 10 mg (extended release formulation) were performed in Indian volunteers to confirm that adequate plasma concentrations are obtained in Indian subjects. Plasma samples were analysed by chromatographic methods. The AUCs of omeprazole were about 3 fold higher and those of felodipine 2 fold higher than AUCs reported in Western subjects. This has no toxicological implications with respect to omeprazole, but whether lower dose of omeprazole may be sufficient in Indian patients with acid related diseases would require acid inhibition studies. In the case of felodipine the higher AUCs in Indian subjects suggest a need for a lower strength formulation (2.5 mg) to fine-titrate the dosage to obtain optimal antihypertensive effects with minimal adverse effects.
Joseph
T
T
Department of Pharmacology, St John's Medical College, Bangalore.
Gowrishankar
R
R
D000284:Administration, Oral; D000293:Adolescent; D000328:Adult; D000897:Anti-Ulcer Agents / Q000493:pharmacokinetics*; D001682:Biological Availability; D002121:Calcium Channel Blockers / Q000493:pharmacokinetics*; D015736:Felodipine / Q000008:administration & dosage / Q000493:pharmacokinetics*; D006801:Humans; D009853:Omeprazole / Q000008:administration & dosage / Q000493:pharmacokinetics*
D000897:Anti-Ulcer Agents; D002121:Calcium Channel Blockers; D009853:Omeprazole; D015736:Felodipine