Lithium Augmentation of Fluvoxamine in Autistic Disorder: A Case Report

Abstract

Preclinical and clinical evidence suggests that serotonin may be involved in the pathophysiology of autistic disorder. Drugs which facilitate serotonin function have demonstrated relative efficacy in improving social relatedness, diminishing aggressivity, and reducing repetitive thoughts and behaviors in some patients with autism. This single-case report reviews the rationale for the use of lithium augmentation of a serotonin uptake inhibitor, fluvoxamine, in the treatment of autism. A 27-year-old man with autistic disorder was treated with fluvoxamine 200 mg (3 mg/kg) daily for 12 weeks and showed minimal clinical response. When lithium 900 mg daily (0.7 meq/L) was added to the fluvoxamine, a substantial clinical improvement in social relatedness and a marked reduction in aggressive and impulsive behavior were observed after two weeks. At the end of four weeks of treatment with fluvoxamine and lithium, the patient was rated as much improved on the several rating scales. He maintained this clinically meaningful improvement at 12-month follow-up, with no significant adverse effects. Controlled studies of lithium augmentation of treatment with serotonin uptake inhibitors are needed to determine whether this approach might benefit other patients with autistic disorder.