Quetiapine for tamoxifen-induced insomnia in women with breast cancer

Psychosomatics. 2009 Mar-Apr;50(2):159-61. doi: 10.1176/appi.psy.50.2.159.


Background: Insomnia is a frequent adverse effect reported by women taking tamoxifen, an estradiol receptor-antagonist, for breast cancer.

Objective: The authors report on six patients treated with quetiapine, an atypical antipsychotic, for tamoxifen-related insomnia without depression.

Method: Quetiapine was started at 25 mg/day 1 hour before bedtime; dose adjustments upward were made in 25-mg increments, titrated to a maximum dose of 100 mg according to therapeutic response and tolerance.

Results: Five of the six women showed a prompt improvement of their insomnia; this effect was maintained after 6 weeks of treatment.

Discussion: Quetiapine might improve sleep alterations because of its high affinity for serotonergic receptors, enhancing central serotonergic neurotransmission, thus possibly decreasing excitatory glutamatergic transmission.

MeSH terms

  • Breast Neoplasms / complications*
  • Breast Neoplasms / drug therapy
  • Breast Neoplasms / pathology
  • Dibenzothiazepines / therapeutic use*
  • Estrogen Antagonists / adverse effects*
  • Estrogen Antagonists / therapeutic use
  • Female
  • Humans
  • Middle Aged
  • Neoplasm Staging
  • Quetiapine Fumarate
  • Sleep Initiation and Maintenance Disorders* / chemically induced
  • Sleep Initiation and Maintenance Disorders* / complications
  • Sleep Initiation and Maintenance Disorders* / drug therapy
  • Tamoxifen / adverse effects*
  • Tamoxifen / therapeutic use


  • Dibenzothiazepines
  • Estrogen Antagonists
  • Tamoxifen
  • Quetiapine Fumarate