Related Experiment Videos
A warfarin-piroxicam drug interaction
Drug Intelligence & Clinical Pharmacy
|July 1, 1985
Summary
Piroxicam discontinuation led to significant prothrombin time fluctuations in a patient on warfarin therapy. This highlights a potential drug interaction affecting anticoagulation management.
Area of Science:
- Pharmacology
- Clinical Medicine
- Drug Interactions
Background:
- Warfarin is a critical anticoagulant for managing thromboembolic disorders.
- Maintaining stable therapeutic anticoagulation is essential to prevent recurrent events.
- Piroxicam is a nonsteroidal anti-inflammatory drug (NSAID) with potential effects on hemostasis.
Observation:
- A 60-year-old male patient on stable warfarin therapy experienced altered prothrombin times.
- These alterations correlated directly with the discontinuation and reintroduction of piroxicam.
- The patient had a history of recurrent pulmonary embolism and deep venous thrombophlebitis.
Findings:
- Discontinuation of piroxicam resulted in a decrease in prothrombin time, indicating reduced warfarin efficacy.
- Rechallenging with piroxicam led to consistent and clinically significant fluctuations in prothrombin time.
- This suggests a pharmacokinetic or pharmacodynamic interaction between piroxicam and warfarin.
Implications:
- Clinicians should be aware of the potential piroxicam-warfarin interaction.
- Careful monitoring of prothrombin time is necessary when these drugs are co-administered.
- This interaction may necessitate adjustments in warfarin dosage to maintain therapeutic anticoagulation.