REM-suppressing effects of amitriptyline and amitriptyline-N-oxide after acute medication in healthy volunteers: results of two uncontrolled pilot trials.

Almost all tricyclic and tetracyclic antidepressants as well as the MAO (monoamineoxidase) inhibitors suppress REM sleep significantly and sustainedly. This does not seem to be an epiphenomenon of antidepressant pharmacotherapy, since initial REM sleep suppression during pharmacological treatment correlated positively with antidepressant effect after three weeks. Furthermore, selective REM-sleep deprivation (by waking patients) had a marked antidepressive effect in depressed patients. The present study used rapid eye movement (REM) sleep suppression in healthy volunteers as a marker to compare the central nervous effects of 150 mg amitriptylineoxide (AMINO) with those of 75 mg amitriptyline (AMI). Both compounds exerted comparable sleep-inducing effects; suppression of REM sleep tended to be more pronounced after application of AMI, despite the higher dose of AMINO used. While this result is evidence of the immediate central nervous effects of a single dose of AMINO, they seem less marked than those of AMI.