PERSISTENT PAIN ASSOCIATED WITH LONG-TERM INTRATHECAL MORPHINE ADMINISTRATION

A 32-year-old man with chronic intractable right lower extremity pain unresponsive to multiple neurosurgical and pharmacologic treatments, i ncluding intrathecal morphine administration, was successfully treated with sciatic nerve block, discontinuance of opioid therapy, and psych ologic interventions. Plasma and urine ratios of morphine metabolites morphine-3-glucuronide and morphine-6-glucuronide were analyzed at the beginning of our interventions, and the results indicated that morphi ne-3-glucuronide levels were significantly higher than morphine-6-gluc uronide levels. The possible association between the observed morphine metabolite ratio and the intractable pain in patients resistant to op ioids may have potential clinical implications.