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methylnaltrexone

A methyl derivative of noroxymorphone with selective, opioid-receptor antagonistic activity. Methylnaltrexone displaces opioids from peripheral opioid receptors in the gastrointestinal tract, the bladder, and the skin, resulting in decreases in opioid-related constipation, urinary retention, and pruritis, respectively. Methylnaltrexone does not cross the blood-brain barrier and does not affect the centrally-mediated analgesic effect of opioids.
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Synonym:N-methylnaltrexone bromide
quaternary ammonium naltrexone
Abbreviation:MNTX
Chemical structure:17-(cyclopropylmethyl)-4,5alpha-epoxy-3,14-dihydroxy-17-methyl-6-oxomorphinanium
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