Major
Apixaban × Dexamethasone
Direct oral anticoagulants (factor Xa inhibitors)×Glucocorticoids
Mechanism
Dexamethasone is a CYP3A4 and P-glycoprotein inducer. It reduces apixaban (a substrate of both) levels by 30–50%, raising thrombotic event risk.
Symptoms
The patient feels no symptoms. Stroke risk in atrial fibrillation rises, as do deep vein thrombosis and pulmonary embolism risks.
Management
For prolonged systemic dexamethasone, do not increase apixaban (no titration data); switch to warfarin with INR monitoring instead. For short dexamethasone pulse therapy (1–3 days), no clinically significant effect.