Oral administration of dextromethorphan prevents the development of morphine tolerance and dependence in rats.

@article{Mao1996OralAO,
  title={Oral administration of dextromethorphan prevents the development of morphine tolerance and dependence in rats.},
  author={Jianren Mao and Donald D. Price and Frank S. Caruso and Dr. Jaques Mayer},
  journal={Pain},
  year={1996},
  volume={67 2-3},
  pages={361-8}
}
Combined oral administration of morphine sulfate (MS) and the over-the-counter antitussive drug and N-methyl-D-aspartate receptor antagonist dextromethorphan (DM) prevented the development of tolerance to the antinociceptive effects of MS (15, 24, or 32 mg/kg) in rats. This combined oral treatment regimen also attenuated signs of naloxone-precipitated physical dependence on morphine in the same rats. A wide range of ratios of MS to DM (2:1, 1:1, and 1:2) were effective for preventing the… CONTINUE READING