Olanzapine and breast-feeding: changes of plasma concentrations of olanzapine in a breast-fed infant over a period of 5 months

J Psychopharmacol. 2010 Jan;24(1):121-3. doi: 10.1177/0269881108096504. Epub 2008 Sep 18.


We here report on a psychotic mother and her breast-fed infant who was treated with olanzapine. Consecutively olanzapine concentrations in the milk and plasma of the mother and in the infant were measured with tandem mass spectroscopy over a period of five month. The results show a relatively high plasma level in the infant aged four month, probably referring to an immature hepatic transformation system, especially CYP1A2. In the following four months plasma levels of olanzapine decreased to very low, even undetectable concentrations in the infant. The infant developed normally and showed no side effects during the treatment period.

Publication types

  • Case Reports

MeSH terms

  • Adult
  • Antipsychotic Agents / adverse effects
  • Antipsychotic Agents / pharmacokinetics*
  • Antipsychotic Agents / therapeutic use
  • Benzodiazepines / adverse effects
  • Benzodiazepines / pharmacokinetics*
  • Benzodiazepines / therapeutic use
  • Breast Feeding*
  • Cytochrome P-450 CYP1A2 / metabolism
  • Depression, Postpartum / drug therapy
  • Female
  • Humans
  • Infant
  • Male
  • Milk, Human / chemistry
  • Olanzapine
  • Psychotic Disorders / drug therapy
  • Psychotic Disorders / etiology
  • Tandem Mass Spectrometry


  • Antipsychotic Agents
  • Benzodiazepines
  • Cytochrome P-450 CYP1A2
  • Olanzapine