DepoDur + lidocaine

DepoDur + lidocaine represents a specific drug interaction scenario in epidural anesthesia. DepoDur is an extended-release liposomal formulation of morphine sulfate designed for single-dose epidural administration that provides up to 48 hours of post-surgical pain relief. When lidocaine (a local anesthetic) is administered epidurally before DepoDur, it significantly alters DepoDur's pharmacokinetics by increasing the release of morphine from the liposomal carrier. This interaction results in higher peak serum concentrations of morphine and faster time to maximum concentration. Clinical studies have shown that administering DepoDur just 3 minutes after a lidocaine-epinephrine test dose results in approximately 2-3 times higher maximum serum concentration of morphine compared to DepoDur alone. This interaction can be minimized by waiting at least 15 minutes between the lidocaine test dose and DepoDur administration. DepoDur is indicated for the treatment of pain following major surgery, including cesarean section, lower abdominal surgery, and major orthopedic surgery of the lower extremities.