Comparison of Intravenous Morphine Versus Paracetamol in Sciatica: A Randomized Placebo Controlled Trial

Acad Emerg Med. 2016 Jun;23(6):674-8. doi: 10.1111/acem.12956. Epub 2016 May 11.

Abstract

Objective: The objective was to compare intravenous morphine and intravenous acetaminophen (paracetamol) for pain treatment in patients presenting to the emergency department with sciatica.

Methods: Patients, between the ages of 21 and 65 years, suffering from pain in the sciatic nerve distribution and a positive straight leg-raise test composed the study population. Study patients were assigned to one of three intravenous interventions: morphine (0.1 mg/kg), acetaminophen (1 g), or placebo. Physicians, nurses, and patients were blinded to the study drug. Changes in pain intensity were measured at 15 and 30 minutes using a visual analog scale. Rescue drug (fentanyl) use and adverse effects were also recorded.

Results: Three-hundred patients were randomized. The median change in pain intensity between treatment arms at 30 minutes were as follows: morphine versus acetaminophen 25 mm (95% confidence interval [CI] = 20 to 29 mm), morphine versus placebo 41 mm (95% CI = 37 to 45 mm), and acetaminophen versus placebo 16 mm (95% CI = 12 to 20 mm). Eighty percent of the patients in the placebo group (95% CI = 63.0% to 99%), 18% of the patients in the acetaminophen group (95% CI = 10.7% to 28.5%), and 6% of those in the morphine group (95% CI = 2.0% to 13.2%) required a rescue drug. Adverse effects were similar between the morphine and acetaminophen groups.

Conclusion: Morphine and acetaminophen are both effective for treating sciatica at 30 minutes. However, morphine is superior to acetaminophen.

Publication types

  • Comparative Study
  • Randomized Controlled Trial

MeSH terms

  • Acetaminophen / administration & dosage
  • Acetaminophen / therapeutic use*
  • Administration, Intravenous
  • Adult
  • Aged
  • Analgesics, Non-Narcotic / administration & dosage
  • Analgesics, Non-Narcotic / therapeutic use*
  • Analgesics, Opioid / administration & dosage
  • Analgesics, Opioid / therapeutic use*
  • Double-Blind Method
  • Emergency Service, Hospital
  • Female
  • Humans
  • Male
  • Middle Aged
  • Morphine / administration & dosage
  • Morphine / therapeutic use*
  • Pain Measurement
  • Sciatica / drug therapy*

Substances

  • Analgesics, Non-Narcotic
  • Analgesics, Opioid
  • Acetaminophen
  • Morphine