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Updated: Aug 8, 2026
07:23
Assessment of Morphine-induced Hyperalgesia and Analgesic Tolerance in Mice Using Thermal and Mechanical Nociceptive Modalities
Published on: July 29, 2014
Magnesium sulfate potentiates morphine antinociception at the spinal level
J S Kroin1, R J McCarthy, N Von Roenn
1Department of Anesthesiology, Rush Medical College at Rush-Presbyterian-St. Luke's Medical Center, Chicago, Illinois 60612, USA.
Anesthesia and Analgesia
|March 29, 2000
Summary
Intrathecal magnesium sulfate enhances morphine
Area of Science:
- Neuroscience
- Pharmacology
- Pain Management
Background:
- Morphine is a primary analgesic, but its efficacy can be limited by tolerance.
- Magnesium sulfate has shown potential in modulating pain pathways.
Purpose of the Study:
- To investigate the antinociceptive interaction between intrathecal magnesium sulfate and morphine.
- To determine if magnesium sulfate potentiates morphine analgesia or mitigates tolerance.
Main Methods:
- Rats received intrathecal (IT) magnesium sulfate or saline, followed by IT morphine or saline.
- Antinociception was assessed using the tail-flick test in morphine-naïve rats.
- Mechanical allodynia was evaluated in rats with incisional pain.
Main Results:
- IT magnesium sulfate significantly enhanced peak antinociception and the overall analgesic effect of morphine in normal rats.
- In rats with incisional pain, IT magnesium sulfate reduced mechanical allodynia, an effect not observed with morphine alone.
Conclusions:
- Intrathecal magnesium sulfate potentiates morphine analgesia at a spinal level.
- Magnesium sulfate may serve as a valuable adjunct to spinal morphine for improved pain management.
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