Paroxetine - A review of its pharmacology and therapeutic potential in the management of panic disorder

Paroxetine is the first selective serotonin (5-hydroxytrypamine; 5-HT) reuptake inhibitor (SSRI) to be approved for the treatment of patients with panic disorder with or without agoraphobia. It is a highly selective inhibitor-of presynaptic serotonin reuptake and does not interact with adrenergic, dopaminergic, histaminergic or serotonergic receptors to any significant extent. Oral paroxetine 10 to 60 mg/day is significantly more effective than placebo in reducing the frequency of panic attacks and improving associated symptoms, as shown in short term trials In patients with panic disorder. with of without agoraphobia. The efficacy of the drug was maintained during Icp to 6 months' treatment, and continued therapy reduced the risk of relapse. Oral paroxetine 10 to 60 mg/day was at least as effective as clomipramine 10 to 150 mg/day, but appeared to have a more rapid onset of effect, in a placebo-controlled trial. The tolerability profile of paroxetine is similar to that established for other SSRls and is characterised by adverse events such as nausea, headache, somnolence, dry mouth, tremor insomnia, asthenia, sweating, constipation, dizziness and sexual dysfunction. Paroxetine was better tolerated overall than clomipramine and was associated with a lower incidence of certain anticholinergic events (such as dry mouth and constipation) in a comparative trial. It is not associated with the type of dependence seen with benzodiazepines, and it appears to be safer in overdose than the tricyclic antidepressants. Paroxetine 20 or 30mg does not significantly impair psychomotor function or interact with alcohol (ethanol). In conclusion, the good tolerability profile of paroxetine, including lack of dependence potential and relative safety in overdose, makes it attractive for the treatment of patients with panic disorder: It appears to be at least as effective as clomipramine in reducing panic attacks and associated symptoms. Although further trials to compare the efficacy and tolerability of paroxetine with that of other tricyclic agents (especially imipramine), high-potency benzodiazepines and monoamine oxidase inhibitors are needed the drug appears to have the potential to become a first-line treatment for panic disorder .