Patients receiving
methadone maintenance
therapy (
MMT) for
opiate dependence have altered nociception, complicating
analgesic treatment. Increasing numbers of patients are choosing
opiate-free treatment programs, yet data on the course of this abnormality months after detoxification from
methadone is contradictory and based exclusively on cold pressor experiments. Heat and pain thresholds were measured by quantitative sensory testing (QST) in 23 subjects with
heroin dependence in full, sustained remission months after detoxification from
methadone and 27 healthy non-
drug using controls. Self reports of
pain intensity and unpleasantness were also collected. Test scores were compared across groups and correlated with measures of
drug use history. There were significant differences between remitted
opiate-dependent subjects and controls on the measures of heat threshold (38.83 vs. 35.96; Mann-Whitney U=177.5, p=0.006), and the measure of pain threshold (48.73 vs. 47.62; Mann-Whitney U=217.5, p=0.043). There was no correlation of any measure of
drug use history with the heat or
pain experience. Abstinent, formerly
opioid-dependent patients continue to demonstrate abnormal noxious perception months after detoxification from
methadone.