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L S Austin

Publications and source records attributed to L S Austin.

7 recordsLinked to original sources

Dopamine blocking activity of clomipramine in patients with obsessive-compulsive disorder.

While many data suggest that Obsessive-Compulsive Disorder (OCD) is an illness accompanied by dysregulation of the serotonergic system, interesting clinical evidence and animal studies also suggest possible dysregulation of the dopaminergic (DA) system. In order to determine whether clomipramine (CMI), an antiobsessional agent, is capable of altering DA function, we performed a neuroleptic radioreceptor assay (NRRA) on plasma samples from OCD patients before and after treatment in a double-blind, placebo controlled trial of CMI. CMI produced mild but significant DA D-2 receptor binding activity in an in vitro assay. The degree of dopamine binding activity did not correlate with clinical response to clomipramine. Because it has been suggested that another drug with antiobsessional efficacy, fluoxetine, may also have dopamine blocking properties, it may be speculated that antidopaminergic activity in combination with serotonergic effects is involved in antiobsessional activity of effective agents for some patients.

Adolescent

Clomipramine: an antiobsessional tricyclic antidepressant.

The chemistry, pharmacology, pharmacokinetics, adverse effects, and dosage of clomipramine hydrochloride are described, and clinical studies of the use of clomipramine in treating obsessive-compulsive disorder (OCD), other psychiatric conditions, and chronic pain are reviewed. Clomipramine hydrochloride, a tricyclic antidepressant, is a potent inhibitor of serotonin reuptake and may affect dopaminergic neurotransmission, suppress rapid eye movement sleep, produce changes in electrocardiograms, and elevate plasma prolactin. The drug is well absorbed from the gastrointestinal tract and undergoes extensive first-pass metabolism. Peak plasma concentrations occur three to four hours after a 150-mg oral dose. The mean elimination half-life is 39 hours. Some 66% of a dose is excreted in the urine, the remainder being eliminated in the feces. In clinical trials, clomipramine was significantly more effective than placebo, clorgiline, amitriptyline, imipramine, and doxepin in ameliorating the symptoms of OCD. Initial effects are seen at four weeks; improvement may continue for up to 18 weeks. Clomipramine may also be effective in treating panic attacks, phobias, depression, and chronic pain. The most common adverse effects of clomipramine are anticholinergic; others include nausea, seizures, and sexual difficulties. Interactions between clomipramine and barbiturates, haloperidol, monoamine oxidase inhibitors, and cigarette smoking have been documented. The usual initial adult dosage is 25-50 mg/day, titrated gradually to 250 mg/day if necessary. Clomipramine hydrochloride is a welcome new agent for the treatment of obsessive-compulsive disorder. Although its adverse-effect profile is like that of other tricyclic antidepressants, sexual dysfunction and seizures may be more frequent with this agent and limit its use.

Clomipramine

Panic and phobic disorders in patients with obsessive compulsive disorder.

Obsessive compulsive disorder shares numerous clinical features with other anxiety disorders. To study the relationship between OCD and other anxiety disorders, the authors administered the Structured Clinical Interview for DSM-III to 36 OCD patients. Thirty-nine percent (14) of patients reported a lifetime history of panic attacks, and 14% (5) met DSM-III-R criteria for panic disorder at the time of interview. Fourteen percent (5) met criteria for social phobias, and 19% (7) met criteria for simple phobias. Eighteen patients were treated with clomipramine in doses of at least 100 mg/day for 3 months. Patients with a history of other anxiety disorders responded significantly better to clomipramine.

Acute Disease