anturane and Levomethadyl acetate Interactions

Interactions between anturane(sulfinpyrazone) and Levomethadyl acetate (levomethadyl acetate)

sulfinpyrazone and levomethadyl acetate (Major Drug-Drug)

MONITOR CLOSELY: Coadministration with inducers of CYP450 3A4 may increase the peak activity and/or decrease the duration of action of levomethadyl acetate, which is primarily metabolized by the isoenzyme. Induction of CYP450 3A4 also results in increased formation of the active metabolites, nor-LAAM and dinor-LAAM. High plasma levels of these metabolites may increase the risk of QT interval prolongation and serious ventricular arrhythmias such as torsades de pointes.

MANAGEMENT: Close monitoring is recommended if levomethadyl acetate is used in combination with a CYP450 3A4 inducer. The dose or dosing interval may require adjustment if an interaction is suspected. A 12-lead ECG should be performed before initiating levomethadyl acetate therapy, 12 to 14 days after initiating therapy, and periodically thereafter. Patients should be advised to seek immediate medical attention if they experience symptoms that could indicate the occurrence of torsade de pointes such as dizziness, palpitations, or syncope.