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Multiple doses of trandolapril do not affect warfarin pharmacodynamics
B H Meyer1, F O Müller, P N Badenhorst
1Department of Pharmacology, University of Orange Free State, Bloemfontein.
Summary
Trandolapril, an angiotensin-converting enzyme inhibitor, did not alter the effects of warfarin, an anticoagulant. This study found no significant pharmacodynamic interactions between these two medications.
Area of Science:
- Pharmacology
- Clinical Pharmacology
- Drug Interactions
Background:
- Warfarin is a widely used anticoagulant.
- Trandolapril is a novel angiotensin-converting enzyme (ACE) inhibitor.
- Understanding potential drug interactions is crucial for patient safety.
Purpose of the Study:
- To investigate the pharmacodynamic effects of trandolapril on warfarin.
- To assess the safety of co-administering trandolapril with warfarin.
Main Methods:
- A double-blind, placebo-controlled, cross-over study was conducted in 19 healthy men.
- Subjects received either trandolapril (2 mg daily) or placebo for 13 days, with warfarin (25 mg) administered on day 8 of each period.
- Prothrombin time (PT) and coagulation factors II, VII, IX, and X were measured sequentially.
Main Results:
- Concomitant administration of trandolapril did not significantly alter warfarin's effect on prothrombin time (PT).
- The ratio of treatment means for PT was 97% (90% CI: 90%-103%) for warfarin + trandolapril versus warfarin + placebo.
- Similarly, factor VII levels showed no significant change (97%, 90% CI: 91%-102%).
Conclusions:
- Trandolapril does not affect the pharmacodynamics of warfarin.
- Co-administration of trandolapril and warfarin appears safe from a pharmacodynamic interaction perspective.
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