Effect of bile acids on absorption of nitrendipine in healthy subjects.
OBJECTIVE
To examine whether bile acids such as ursodeoxycholic acid (UDCA) and chenodeoxycholic acid (CDCA) can influence the absorption of nitrendipine, a highly lipophilic calcium channel blocker.


METHODS
Six healthy subjects received nitrendipine (10 mg) with and without UDCA (50 mg) and CDCA (200 and 600 mg) with an interval of 1 approximately 2 weeks between study phases.


RESULTS
Bile acids decreased the Cmax (ng ml(-1)) [control 10.9 +/- 5.8 (mean+/- s.d.), UDCA 5.0 +/- 4.7 (95% confidence interval for difference; 3.9, 7.8, P = 0.0006), CDCA (600 mg) 5.0 +/- 3.9 (2.6, 9.2, P = 0.0059)] and AUC (ng ml(-1) h) [(control; 60 +/- 36, UDCA 15 +/- 13 (20, 73, P = 0.0064), CDCA (600 mg) 19 +/- 19 (21, 63, P = 0.0038)] of nitrendipine, while elimination half-life remained unchanged.


CONCLUSIONS
These results suggest that the amount of nitrendipine absorbed was decreased when the drug was administered with UDCA and CDCA.
Sasaki
M
M
Department of Clinical Pharmacology, Jichi Medical School, Tochigi 329-0498, Japan.
Maeda
A
A
Sakamoto
K
K
Fujimura
A
A
D000328:Adult; D019540:Area Under Curve; D001647:Bile Acids and Salts / Q000494:pharmacology*; D002121:Calcium Channel Blockers / Q000008:administration & dosage / Q000097:blood / Q000493:pharmacokinetics* / Q000627:therapeutic use; D002635:Chenodeoxycholic Acid / Q000494:pharmacology; D002756:Cholagogues and Choleretics / Q000494:pharmacology*; D004347:Drug Interactions; D006801:Humans; D008297:Male; D009568:Nitrendipine / Q000008:administration & dosage / Q000097:blood / Q000493:pharmacokinetics* / Q000627:therapeutic use; D013997:Time Factors; D014580:Ursodeoxycholic Acid / Q000494:pharmacology
D001647:Bile Acids and Salts; D002121:Calcium Channel Blockers; D002756:Cholagogues and Choleretics; D002635:Chenodeoxycholic Acid; D014580:Ursodeoxycholic Acid; D009568:Nitrendipine