The effect of intrathecal magnesium sulphate on nociception in rat acute pain models

Anaesthesia. 1999 Mar;54(3):241-6. doi: 10.1046/j.1365-2044.1999.00741.x.


We examined the antinociceptive effect of intrathecally administered magnesium sulphate (MgSO4) in rats, using acute pain models including mechanical pressure, heat and subcutaneous formalin injection. According to the locomotion test 10 microliters of 6.2% MgSO4 did not produce motor paralysis. At the same dose, responses to pressure and heat were intact, compared with controls given saline. MgSO4 produced depression of pain responses only after the first 10 min in the formalin test. Our studies indicated that MgSO4 did not show remarkable antinociceptive effects in acute pain models.

MeSH terms

  • Acute Disease
  • Analgesics / therapeutic use*
  • Animals
  • Dose-Response Relationship, Drug
  • Hot Temperature
  • Locomotion / drug effects
  • Magnesium Sulfate / therapeutic use*
  • Male
  • Pain / drug therapy*
  • Pain / etiology
  • Pain Measurement
  • Pressure
  • Rats
  • Rats, Wistar


  • Analgesics
  • Magnesium Sulfate