simvastatin and Delavirdine Interactions

Interactions between simvastatin and Delavirdine (delavirdine)

simvastatin and delavirdine (Major Drug-Drug)

GENERALLY AVOID: Delavirdine may significantly elevate the plasma concentrations of HMG-CoA reductase inhibitors. The mechanism is decreased clearance due to inhibition of CYP450 3A4 metabolism by delavirdine. Myopathy manifested as muscle pain and/or weakness associated with grossly elevated creatine kinase has been reported occasionally with the use of HMG-CoA reductase inhibitors. Rhabdomyolysis has also occurred rarely, which may be accompanied by acute renal failure secondary to myoglobinuria.

MANAGEMENT: Because of the increased risk of musculoskeletal toxicity associated with high levels of HMG-CoA reductase inhibitory activity in plasma, concurrent use is not recommended by the manufacturer. If patients do receive this combination, they should be closely monitored for early signs of myopathy and advised to report symptoms of muscular pain, weakness, tenderness, malaise, or fever. Pravastatin may be a safer alternative, since it is metabolized by a different pathway.