Naloxone improves sleep apnea in obese humans.

To test the hypothesis that endogenous opiates play a role in the etiology of the sleep apnea syndrome, we administered naloxone, an opiate antagonist, to ten obese humans with sleep apnea. On two separate nights we measured the frequency and severity of sleep apnea during naloxone infusion vs saline control infusion. The number of oxyhemoglobin desaturation episodes was not significantly lowered but the average maximal oxyhemoglobin desaturation fell significantly (P less than 0.01) with naloxone. The desaturation index (average maximal oxyhemoglobin desaturation times desaturations per hour) fell by 21 percent (P less than 0.05) on the night of naloxone infusion. Nine of the ten patients had a lower desaturation index with naloxone. REM sleep decreased by 80 percent (P less than 0.05) in the subjects in whom it was measured. We conclude that opiate antagonists hold promise in the treatment of sleep apnea and that the endogenous opiate system may be involved in the production of sleep apnea.