Efficacy and safety of single and repeated administration of 1 gram intravenous acetaminophen injection (paracetamol) for pain management after major orthopedic surgery.

Background: Intravenous acetaminophen injection (paracetamol) is marketed in Europe for the management of acute pain. A repeated-dose, randomized, double-blind, placebo-controlled, three-parallel group study was performed to evaluate the analgesic efficacy and safety of intravenous acetaminophen as compared with its prodrug (propacetamol) and placebo. Propacetamol has been available in many European countries for more than 20 yr.

The COX-2 specific inhibitor, valdecoxib, is an effective, opioid-sparing analgesic in patients undergoing total knee arthroplasty.

This multicenter, randomized, double-blind, placebo-controlled study evaluated the analgesic efficacy and opioid-sparing effects of valdecoxib, a potent COX-2 specific inhibitor, in patients undergoing knee replacement. Patients received morphine by patient-controlled analgesia (PCA), and valdecoxib 40 mg or 80 mg daily, or placebo, for up to two days. Efficacy was assessed by the cumulative amount of morphine administered over 48 hours, pain intensity and patient's evaluation of medication.