Epi-inositol: A potential antidepressant

Inositol is a simple polyol precursor in a second messenger system importan t in the brain. A double-blind controlled trial of 12 g daily of inositol i n 28 patients with depression for 4 weeks found significant benefit for ino sitol compared to placebo on the Hamilton Depression Scale. Because many an tidepressants are effective in panic disorder, 21 patients with this disord er completed a double-blind, placebo-controlled crossover treatment trial o f inositol 12 g per day. Frequency and severity of panic attacks and severi ty of agoraphobia declined significantly with inositol treatment compared t o placebo. Because serotonin reuptake inhibitors benefit obsessive-compulsi ve disorder (OCD) and inositol is reported to reverse desensitization of se rotonin receptors, 13 patients with OCD completed a double-blind, controlle d crossover trial of 18 g inositol or placebo for 6 weeks each. Inositol si gnificantly reduced scores of OCD symptoms compared with placebo. Epi-inosi tol, an artificial stereoisomer of myoinositol, was found to have effects s imilar to those of myoinositol in reversing lithium-pilocarpine seizures an d in reversing lithium-induced rises in cytidine monophosphorylphosphatidat e in cultured cells as does myoinositol. We measured the behavior of rats i n an elevated plus-maze model of anxiety after chronic treatment of 11 dail y ip injections of epi-inositol, myoinositol, or control solution. Epi-inos itol reduced anxiety levels of rats compared with controls, and its effect was stranger than that of myoinositol. Epi-inositol could be a more effecti ve psychoactive drug than its natural analog. Drug Dev. Res. 50:309-315, 20 00. (C) 2000 Wiley-Liss, inc.