Cortisol levels during chronic naltrexone maintenance treatment in ex-opiate addicts

Abstract

Several studies have shown a rise in cortisol and adrenocorticotropic hormone (ACTH) in response to a bolus administration of an opioid antagonist (Volavka et al. 1978, 1979; Judd et al. 1981; Nabor et al. 1981). This has fit well with the lowering of cortisol and ACTH levels that has been observed following the acute administration of all opiates and the chronic use of short-acting opiates (Chusman and Kreek 1974). However, during chronic treatment with a long-acting opiate, i.e., methadone, cortisol levels return to normal after several months (Cushman and Kreek 1974; Kreek 1978). Thus, the question has arisen whether or not chronic treatment with a long-acting opioid antagonist would result in a persistent elevation of cortisol levels, as has been found acutely. Therefore, we measured diurnal variation in cortisol levels in former opiate addicts who were being maintained for at least 15 weeks on naltrexone, a long-acting orally effective opioid antagonist.