Effect of dehusked Garcinia kola seeds on the overall pharmacokinetics of quinine in healthy Nigerian volunteers.
We investigated the effect of concurrent ingestion of Garcinia kola seed on the pharmacokinetics of quinine. In a randomized crossover study, 24 healthy Nigerian volunteers were assigned into 2 groups (A and B; n = 12 per group) on the basis of G. kola dose orally ingested. Each subject received 600 mg quinine sulfate before and after ingesting 12.5 g of G. kola once daily for 7 days (group A) or 12.5 g twice daily for 6 days and once on the seventh day (group B). Blood samples were collected and analyzed for plasma quinine and its metabolite (3-hydroxyquinine) using a validated high performance liquid chromatography method. Concurrent administration of quinine with G. kola reduced quinine tmax by 48% (group A), mean Cmax by 19% and 26% in groups A and B, respectively, and slight reduction in mean AUC0- ∞ of quinine in both groups. 3-hydroxyquinine Cmax also reduced by 29% and 32%; AUC0-∞ by 13% and 9%, respectively. The point estimates of the T/R ratio of the geometric means for all Cmax obtained and only the AUC0-∞ at a higher dose of G. kola were outside the 80%-125% bioequivalence range. In conclusion, an herb-drug interaction was noted with concurrent quinine and G. kola administration.
['Igbinoba|Sharon I|SI|', 'Onyeji|Cyprian O|CO|', 'Akanmu|Moses A|MA|', 'Soyinka|Julius O|JO|', 'Pullela|Srirama Sarma V V|SS|', 'Cook|James M|JM|', 'Nathaniel|Thomas I|TI|']
D000284:Administration, Oral D000328:Adult D019540:Area Under Curve D001711:Biotransformation D002851:Chromatography, High Pressure Liquid D018592:Cross-Over Studies D019587:Dietary Supplements D004347:Drug Interactions D005260:Female D029763:Garcinia kola D006207:Half-Life D064368:Healthy Volunteers D006801:Humans D008297:Male D008657:Metabolic Clearance Rate D009549:Nigeria D011802:Quinidine D011803:Quinine D012639:Seeds D013810:Therapeutic Equivalency D055815:Young Adult
Garcinia kola pharmacokinetics quinine 3-hydroxyquinine drug-herb interactions