Clomipramine. An overview of its pharmacological properties and a review of its therapeutic use in obsessive compulsive disorder and panic disorder

During the 20 years that have elapsed since clomipramine (chlorimipramine) was first marketed, it has become well established in the treatment of depressive illness, particularly treatment-resistant depression. However, in addition to its role as an antidepressant, attention is being focused on the use of clomipramine in 2 other areas of psychiatry: obsessive compulsive disorder and panic disorder. Short term clinical trials have shown that clomipramine is generally more effective than amitriptyline, imipramine, desipramine, nortriptyline or clorgiline in reducing obsessive compulsive symptoms. Clomipramine appears to produce some short term benefit with exposure therapy in patients with obsessive compulsive disorder. However, the efficacy of the drug after long term follow-up has not been fully investigated. The antiobsessional efficacy of clomipramine appears to be independent of its antidepressant activity. In patients with panic disorder with or without agoraphobia (DSM-IIIR), clomipramine reduces the frequency and severity of panic attacks within 7 to 21 days of beginning treatment and efficacy is maintained for at least 12 months. Clomipramine is more effective than imipramine, the generally accepted standard treatment for patients with panic disorder after 2 weeks' treatment, but after 6 or 10 weeks both drugs are similarly effective. Other double-blind studies have shown that clomipramine is more effective than placebo and at least as effective as fluvoxamine and oxitriptan (5-hydroxytryptophan) in reducing panic attacks and associated anxiety. Adverse effects associated with clomipramine treatment are mild to moderate in nature and are predominantly a result of the drug's anticholinergic activity. The incidence of seizures is dose related, occurring in 0.48% of all patients receiving clomipramine less than or equal to 250 mg/day and 2.1% of patients receiving greater than or equal to 300 mg/day. In conclusion, the available data indicate that clomipramine is a worthwhile addition to the limited treatments available for obsessive compulsive disorder and panic disorder, two psychiatric disorders which have previously been difficult to manage pharmacologically.