| Drug Interactions between Theophylline and H2-antagonists; Ranitidine, Famotidine |
|
Sang Heon Cho1, Young Joo Cho1, Mi Kyeong Kim1, O Jung Kwon1, Choon Taek Lee1, Sang Do Lee1, Kyung Up Min1, You Young Kim1, Ho Soon Kim2, Hyun Taek Shin2 |
1Department of Internal Medicine, College of Medicine, Seoul National University, Seoul, korea
2Drug Information Center, Seoul National University Hospital, Seoul, korea |
| Ranitidine과 Famotidine이 Theophylline 대사에 미치는 영향의 약동학적 비교연구 |
|
조상헌1, 조영주1, 김미경1, 권오정1, 이춘택1, 이상도1, 민경업1, 김유영1, 김호순2, 신현택2 |
|
|
|
|
| Abstract |
|
Among the H2 antagonists, cimetidine is known to impair theophylline metabolism. But there are some controversies about the effects of ranitidine and famotidine on theophylline pharmacokinetics We experienced a 53-year-old male patient who showed significant decrease of theophylline clearance with ranitidine and recovery after raniticline withdrawal. To investigate drug interactions between ranticline, famotidine and theophylline, six healthy adults were given a 6 mg/ kg aminophylline intravenously on three occasions, without H2-antagonists, with ranitidine 300 mg/ clay, with famotidine 40 mg/ clay for 4 clays. and serum theophylline levels were measured at 0, 1/ 4, 1/ 2, 1, 2, 4, 8, and 24 hour after aminophylline infusion. Ranitidine and famotidine administrations were cross-overed. Ranitidine decreased theophylline clearance by 14% (range 1% to 22%) and increased elimination half-life by 36% (range 20%to 50%). Our data suggest that clinically significant inhibition of theophylline metabolism by raniticline is largely dependent on pretreatment theophylline clearance Famotidine did not significantly alter theophylline pharmacokinetics, but there was great individual variability. We suggest that regular estimations of serum theophylline level is necessary to avoid theophylline toxicity with H2-antagonists; ranitidine and famotidine. |
|
PDF Links
Full text via DOI
Download Citation
