Stability of opioid craving over time as measured by visual analog scales.

Sixteen methadone maintenance patients reported their 24-h peak opioid craving on a visual analog scale and the time of day at which the peak craving occurred on weekdays over a 4-week period. Both intersubject and intrasubject craving scores were highly variable. Craving scores did not correlate highly with time since the previous dose, mean methadone dose, requests for changes in maintenance dose, or occurrence of positive urine-drug screens. These data suggest that 24-h craving recall (as measured by visual analog scales) varies over time and is not closely correlated with changes in methadone blood levels.