Pain management in emergency department: intravenous morphine vs. intravenous acetaminophen

Pain is the most common complaint in emergency department and there are several methods for its control. Among them, pharmaceutical methods are the most effective. Although intravenous morphine has been the most common choice for several years, it has some adverse effects. There are many researches about intravenous acetaminophen as an analgesic agent and it appears that it has good analgesic effects for various types of pain. We searched some electronic resources for clinical trials comparing analgesic effects of intravenous acetaminophen vs. intravenous morphine for acute pain treatment in emergency setting.In two clinical trials, the analgesic effect of intravenous acetaminophen has been compared with intravenous morphine for renal colic. The results revealed no significant difference between analgesic effects of two medications. Another clinical trial revealed that intravenous acetaminophen has acceptable analgesic effects on the post-cesarean section pain when combined with other analgesic medications. One study revealed that administration of intravenous acetaminophen compared to placebo before hysterectomy decreased consumption of morphine via patient-controlled analgesia pump and decreased the side effects. Similarly, another study revealed that the infusion of intravenous acetaminophen vs. placebo after orthopedic surgery decreased the consumption of morphine after the surgery. A clinical trial revealed intravenous acetaminophen provided a level of analgesia comparable to intravenous morphine in isolated limb trauma, while causing less side effects than morphine.It appears that intravenous acetaminophen has good analgesic effects for visceral, traumatic and postoperative pains compare with intravenous morphine.