Individual variations in response of human REM sleep to amitriptyline and haloperidol

The effect of amitriptyline and haloperidol on REM sleep was investigated in healthy human adults, with special attention to individual variations in these drugs' effects. In addition, an investigation was made of the rebound elevation of REM sleep occurring on the following night of partial differential REM deprivation (PDRD), again with emphasis being placed on individual variations in that effect. The administration of amitriptyline in a single oral dose of 25 mg was followed by an inhibition of REM sleep in all subjects. The per cent decrease in REM sleep was found to have a significant negative correlation with the per cent increase in REM sleep following PDRD in individual subjects. The amount of REM sleep during the recovery night following the night of amitriptyline medication tended to correlate with the per cent increase in REM sleep following PDRD in individual subjects. Haloperidol in a single oral dose of 1.5 mg caused REM sleep to augment in some subjects but inhibit in others. A significant correlation was noted to exist between drug-induced change in REM sleep and the per cent increase in REM sleep following PDRD.