Double-blind, controlled, crossover trial of inositol versus fluvoxamine for the treatment of panic disorder

Only 70% of patients respond to current treatments for panic disorder, and many discontinue drugs because of side effects. myo-Inositol, a natural iso mer of glucose and a precursor for the second-messenger phosphatidyl-inosit ol system, has previously been found superior to placebo in the treatment o f depression, panic disorder, and obsessive-compulsive disorder (OCD), but a direct comparison with an established drug has never been performed. A do uble-blind, controlled, random-order crossover study was undertaken to comp are the effect of inositol with that of fluvoxamine in panic disorder, Twen ty patients completed 1 month of inositol up to 18 g/day and I month of flu voxamine up to 150 mg/day. Improvements on Hamilton Rating Scale for Anxiet y scores, agoraphobia scores, and Clinical Global Impressions Scale scores were similar for both treatments. In the first month, inositol reduced the number of panic attacks per week (mean and SI)) by 4.0 (2) compared with a reduction of 2.4 (2) with fluvoxamine (p = 0.049), Nausea and tiredness wer e more common with fluvoxamine (p = 0.02 and p = 0.01, respectively). Becau se inositol is a natural compound with few known side effects, it is attrac tive to patients who are ambivalent about taking psychiatric medication. Co ntinuing reports of inositol's efficacy in the treatment of depression, pan ic disorder, and OCD should stimulate replication studies.