June 2007

rTMS: Inferior to ECT?
Repetitive transcranial magnetic stimulation (rTMS) is not as efficacious as electroconvulsive therapy (ECT) in patients referred for ECT.

Psychotropics and Fracture Risk
Patients (especially elderly ones) taking psychiatric medications are at increased risk for fractures.

Riluzole Augmentation for Depression
Preliminary evidence suggests riluzole (Rilutek) may be helpful in treating mood and anxiety disorders.

CBT Beats Zopiclone for Insomnia in Elderly
Cognitive behavioral therapy (CBT) was superior to zopiclone (Ambien) for chronic primary insomnia.

Alternative Medicines Are Commonly Used
Surveys show alternative medicines used by more than half of US population.

Hyponatremia with Antidepressants
Hyponatremia reported in patients treated with escitalopram (Lexapro) or duloxetine (Cymbalta).

In Brief
Dosing Strategies for Risperidone Long-Acting Injection; Deaths Associated with Methadone Treatment for Pain

Prolactin Levels and Associated Side Effects with Risperidone
Initial elevation of prolactin levels with risperidone (Risperdal) returns to normal with long-term treatment.

Mifepristone for Psychotic Depression?
Treatment with mifepristone (Mifeprex) improves psychosis but not depression in patients with psychotic depression.

An NSAID for Schizophrenia?
Adjunctive celecoxib (Celebrex) may be beneficial for treating schizophrenia.

Prolactin Levels and Associated Side Effects with Risperidone

June 2007

First-generation antipsychotics elevate prolactin levels, presumably by blocking dopamine in the tubero-infundibular pathway. Second-generation antipsychotics are much less likely to raise prolactin, with the exception of risperidone (Risperdal)—which does so in a dose-dependent manner.

Prolactin plays a physiological role in lactation. When serum prolactin levels are pathologically elevated, women may have decreased menstruation, and both men and women report decreased libido. Elevated prolactin might also have adverse effects on bone health.

To assess the effects of long-term risperidone treatment on prolactin levels, Eberhard and colleagues in Sweden took advantage of a longitudinal, multicenter trial.1 At the start of the trial, 128 men and 90 women were being treated for several different psychosis diagnoses with risperidone, most on monotherapy. Prolactin levels were five times higher than normal in women and threefold greater in men. Over 5 years, almost half the patients were switched to other antipsychotics, which were not associated with high prolactin levels. Patients who continued for up to 5 years on risperidone treatment had a substantial linear reduction of prolactin levels. Although sexual side effects were common in both men and women, prolactin levels did not correlate with sexual side effects. Similarly, in another study of men and women treated with antipsychotics for schizophrenia or schizoaffective disorder, sexual dysfunction was not associated with prolactin or gonadal hormone levels.2

Eberhard's group concludes that risperidone markedly elevates prolactin levels, in women more than in men. However, with long-term treatment, prolactin levels tend to return toward normal. Both studies suggest that the actual side effect burden from these elevated levels may be less than previously believed.

1Eberhard J, Lindström E, Holstad M, Levander S: Prolactin level during 5 years of risperidone treatment in patients with psychotic disorders. Acta Psychiatr Scand 2007;115:268-276.

2Howes OD, Wheeler MJ, Pilowsky LS, Landau S, Murray RM, Smith S: Sexual function and gonadal hormones in patients taking antipsychotic treatment for schizophrenia or schizoaffective disorder. J Clin Psychiatry 2007;68:361-367.