Panic disorder: Long-term pharmacotherapy and discontinuation

This article compares panic disorder (PD) medications and discusses long-te rm therapy. In a review of the Literature, monoamine oxidase inhibitors (MA OIs), selective serotonin reuptake inhibitors (SSRIs), and benzodiazepines prove effective in treating PD. MAOIs treat comorbid depression; frequent s ide effects are dizziness and orthostatic hypotension. SSRIs are better tol erated than MAOIs, producing mild anticholinergic effects, but also produci ng gastrointestinal side effects and sexual dysfunction. Benzodiazepines ar e generally well tolerated when titrated gradually; moderate sedation is th e most common shortterm side effect. Long-term risks are physical dependenc e and withdrawal reactions. One hundred six PD patients were enrolled in a double-blind, 8-month, placebo-controlled trial of alprazolam and imipramin e. In the 8-week short-term phase, daily dosages mere titrated up to 10 mg/ day of alprazolam and 250 mg/day of imipramine. The greatest number of drop outs occurred during this phase (lack of improvement and/or side effects). Alprazolam patients had a significantly more rapid onset of improvement and lower adverse events and attrition rates. In the 6-month maintenance perio d, patients continued short-term treatment. Patients receiving either alpra zolam or imipramine developed tolerance to some side effects. At maintenanc e-phase completion, 62% of the alprazolam-group patients and 26% of both th e imipramine- and placebo-group patients were panic free (p < 0.01). Dosage s were tapered to zero over 3 weeks; one third of the alprazolam patients c ould not discontinue. During the unblinded, 15-month follow-up, patients re ceived open treatment selected by personal physicians on an as-needed basis . At the end of follow-up, all patients were reassessed. Patients who had c ompleted both short-term and maintenance phases mere far more likely to be panic-free (85% vs. 55%; p < 0.01). PD is chronic and recurrent, and 8 mont hs is an effective treatment period. Maintenance treatment does not lead to tolerance, even with. benzodiazepines. Dose tapering must be very gradual, Completion of a long-term maintenance program strongly predicts remission.