Effect of a Serotonin and Noradrenaline Uptake Inhibitor in Panic Disorder; a Double-blind Comparative Study with Fluvoxamine and Maprotiline

A double-blind comparative study with fluvoxamine, a specific serotonin uptake inhibitor, and maprotiline, a specific noradrenaline uptake inhibitor, was conducted in 44 patients suffering from panic disorder with or without phobic avoidance. Patients were treated with 150 mg of either fluvoxamine or maprotiline daily for 6 weeks. Fluvoxamine was found to be a potent anti-panic agent. The number of panic attacks decreased significantly during treatment. The level of anxiety showed a noteworthy time course. After an initial increase during the first week of treatment, the level of anxiety declined significantly as compared to baseline on continuation of the treatment. The therapeutic properties of fluvoxamine were therefore apparent from week 4 on. In addition, the associated depressive symptomatology decreased as well. Relative to fluvoxamine, maprotiline was ineffective in the treatment of panic disorders. Maprotiline had a slight effect on the depressive symptoms but virtually no effect on the level of anxiety. These findings support the hypothesis that serotonergic pathways in the brain are implicated in the pathogenesis of panic disorders. The data are at variance, however, with findings indicating that drugs that are efficacious in panic disorder act by altering noradrenergic function.