BACKGROUND: Prazosin is an antagonist of alpha-1 adrenergic receptor used to treat PTSD-related nightmares and insomnia. Although evidence suggests that it is also effective in the treatment of general symptoms of PTSD, its short half-life (2-3 hours) may limit its therapeutic effects. OBJECTIVE: To describe four cases of patients with PTSD resistant to selective serotonin reuptake inhibitors (SSRIs) or selective serotonin/noradrenaline reuptake inhibitor (SNRIs) therapy (conventional therapy) treated with slow-release prazosin presentation. METHODS: Four patients with severe PTSD resistant to conventional therapy received slow-release prazosin (half-life of 10.8 hours) added to their prescription for at least three months. PTSD symptoms were evaluated by the PCL-C, together with nightmares and insomnia items of CAPS, at baseline and at the last observation of each patient. RESULTS: Two patients showed improvement in general symptoms of PTSD (reduction of 35.7% and 11.9% in PCL-C scores), and three showed relief from nightmares and insomnia (CAPS scores). The only patient who received morning and bedtime doses of prazosin showed the greatest improvement in general symptoms of PTSD. DISCUSSION: It is possible that the sustained blockade of noradrenergic activity in the central nervous system provided by slow-release prazosin during the day is necessary to further ameliorate residual PTSD symptoms in patients receiving conventional antidepressant therapy.
Posttraumatic stress disorder; prazosin; pharmacotherapy; PTSD; alpha-1 adrenergic antagonist
