Drug Interaction Report

MONITOR: Propoxyphene may increase the serum levels of some oral beta-blockers. The proposed mechanism is inhibition of CYP450 2D6 first-pass metabolism and decreased hepatic clearance. Data are available for metoprolol and propranolol only; however, other hepatically metabolized beta-blockers may also be affected. Renally excreted beta-blockers such as atenolol, carteolol, nadolol, or sotalol are not expected to interact.

MANAGEMENT: Patients receiving this combination should be monitored for hypotension, heart failure, bradycardia, arrhythmias, and mental status changes when propoxyphene is added to the patient's medical regimen, and for decreased beta-blockade when propoxyphene is deleted from the regimen. A reduction in beta-blocker dosage may necessary.

GENERALLY AVOID: Alcohol may have additive CNS- and/or respiratory-depressant effects with propoxyphene. Misuse of propoxyphene, either alone or in combination with other CNS depressants, has been a major cause of drug-related deaths, particularly in patients with a history of emotional disturbances, suicidal ideation, or alcohol and drug abuse.

MANAGEMENT: The use of alcohol during propoxyphene therapy should be avoided. Patients should be warned not to exceed the recommended dosage of propoxyphene and to avoid activities requiring mental alertness until they know how these agents affect them.