PTSD nightmares: Prazosin and atypical antipsychotics

Comparing prazosin and quetiapine. A historical prospective cohort study of 237 veterans with PTSD receiving prazosin or quetiapine for nighttime PTSD symptoms demonstrated that although the 2 drugs have similar efficacy (defined as symptomatic improvement) for short-term, 6-month treatment (61% vs 62%; P=.54), a higher percentage of patients continued prazosin long-term (3 to 6 years) than those taking quetiapine (48% vs 24%; P < .001).²³ Twenty-five percent of patients taking quetiapine switched to prazosin during the study, and approximately one-half of these patients remained on prazosin until the study’s end. Only 8% of prazosin patients switched to quetiapine, and none continued this therapy until study end.²³ Patients in the quetiapine group were more likely to discontinue the drug because of lack of efficacy (13% vs 3%; P=.03) and adverse effects (35% vs 18%; P=.008), specifically sedation (21% vs 2%; P < .001) and metabolic effects (9% vs 0%; P=.014), compared with prazosin. Although this trial may be the only published comparison study of prazosin and quetiapine, its methodological quality has been questioned, which makes it difficult to draw definitive conclusions.

Metabolic syndrome—elevated diastolic blood pressure, increased waist circumference, and low high-density lipoprotein cholesterol—is common among PTSD patients treated with antipsychotics.²⁴ This syndrome may be caused by medications, lifestyle factors, or long-term overactivation of stress-response pathways. A retrospective chart review at a community mental health center revealed that patients taking even low doses of quetiapine for insomnia gained an average of 5 lbs (P=.037).²⁵ Another retrospective chart review at 2 military hospitals reported that patients receiving low-dose quetiapine (≤100 mg/d) gained an average of slightly less than 1 lb per month, which adds up to approximately 10 lbs per year (P < .001).²⁶ The benefit of using atypical antipsychotics may be outweighed by metabolic risks such as obesity, new-onset diabetes, and dyslipidemia.²⁷

Prazosin is considered a first-line treatment for sleep disturbances and nightmares in PTSD because of its superior long-term efficacy and decreased adverse effects compared with quetiapine.

Related Resources

• American Psychiatric Association. Practice guidelines for the treatment of patients with acute stress disorder and posttraumatic stress disorder. Arlington, VA: American Psychiatric Publishing, Inc.; 2004.
• Veterans Affairs/Department of Defense clinical practice guidelines. Management of traumatic stress disorder and acute stress reaction. www.healthquality.va.gov/Post_Traumatic_Stress_Disorder_PTSD.asp.

Drug Brand Names

• Prazosin • Minipress
• Quetiapine • Seroquel
• Sertraline • Zoloft
• Ziprasidone • Geodon

Disclosure

The authors report no financial relationship with any company whose products are mentioned in this article or with manufacturers of competing products.