Olanzapine acute administration in schizophrenic patients increases delta sleep and sleep efficiency

Biol Psychiatry. 1999 Jul 1;46(1):141-3. doi: 10.1016/s0006-3223(98)00372-2.


Background: A delta sleep deficit has been observed in schizophrenic patients. Olanzapine is a novel atypical antipsychotic agent with affinity at dopaminergic, serotonergic, muscarinic, adrenergic and histaminergic binding sites. The present study was designed to analyze a sleep promoting effect reported for olanzapine.

Methods: Twenty schizophrenic patients (DSM-IV) were studied, who were drug free and inpatients. Patients slept for 5 consecutive nights in the sleep unit as follows: one acclimatization night; two baseline nights (the first for sleep disorder screenings); and two olanzapine nights (10 mg olanzapine, one hour before sleep onset).

Results: Sleep continuity variables and total sleep time showed an overall improvement with olanzapine. Waking time was reduced since the first night of olanzapine administration. The main sleep architecture changes were: reduction in sleep stage 1, while sleep stage 2 and delta were significantly enhanced. Rapid eye movement density was also increased by the second olanzapine night.

Conclusions: Total sleep improvement was due to the increase in sleep stages 2 and delta sleep. This may be related to serotonergic antagonistic properties of olanzapine. Olanzapine seems to have a sleep promoting effect in schizophrenic patients.

MeSH terms

  • Adult
  • Antipsychotic Agents / therapeutic use*
  • Benzodiazepines
  • Delta Rhythm*
  • Dose-Response Relationship, Drug
  • Female
  • Humans
  • Male
  • Olanzapine
  • Pirenzepine / analogs & derivatives*
  • Pirenzepine / therapeutic use
  • Psychiatric Status Rating Scales
  • Schizophrenia / diagnosis
  • Schizophrenia / drug therapy*
  • Sleep, REM / physiology*


  • Antipsychotic Agents
  • Benzodiazepines
  • Pirenzepine
  • Olanzapine