Paroxetine is a
selective serotonin reuptake inhibitor (SSRI), with
antidepressant and
anxiolytic activity. In 6- to 24-week well designed trials, oral
paroxetine 10 to 50 mg/day was significantly more effective than placebo, at least as effective as
tricyclic antidepressants (TCAs) and as effective as other
SSRIs and other
antidepressants in the treatment of
major depressive disorder. Relapse or recurrence over 1 year after the initial response was significantly lower with
paroxetine 10 to 50 mg/day than with placebo and similar to that with
imipramine 50 to 275 mg/day. The efficacy of
paroxetine 10 to 40 mg/day was similar to that of TCAs and
fluoxetine 20 to 60 mg/day in 6- to 12-week trials in patients aged > or = 60 years with major depression.
Paroxetine 10 to 40 mg/day improved depressive symptoms to an extent similar to that of TCAs in patients with comorbid illness, and was more effective than placebo in the treatment of
dysthymia and minor depression.
Paroxetine 20 to 60 mg/day was more effective than placebo after 8 to 12 weeks' treatment of
obsessive-compulsive disorder (OCD),
panic disorder,
social anxiety disorder (
social phobia), generalised
anxiety disorder (GAD) and
post-traumatic stress disorder (
PTSD). Improvement was maintained or relapse was prevented for 24 weeks to 1 year in patients with OCD,
panic disorder,
social anxiety disorder or GAD. The efficacy of
paroxetine was similar to that of other
SSRIs in patients with OCD and
panic disorder and similar to that of
imipramine but greater than that of 2'
chlordesmethyldiazepam in patients with GAD.
Paroxetine is generally well tolerated in adults, elderly individuals and patients with comorbid illness, with a tolerability profile similar to that of other
SSRIs. The most common adverse events with
paroxetine were
nausea, sexual dysfunction,
somnolence,
asthenia,
headache,
constipation,
dizziness, sweating,
tremor and decreased appetite. In conclusion,
paroxetine, in common with other
SSRIs, is generally better tolerated than TCAs and is a first-line treatment option for
major depressive disorder,
dysthymia or minor depression. Like other
SSRIs,
paroxetine is also an appropriate first-line
therapy for OCD,
panic disorder,
social anxiety disorder, GAD and
PTSD. Notably,
paroxetine is the only SSRI currently approved for the treatment of
social anxiety disorder and GAD, which makes it the only
drug of its class indicated for all five
anxiety disorders in addition to
major depressive disorder. Thus, given the high degree of psychiatric comorbidity of depression and anxiety,
paroxetine is an important first-line option for the treatment of
major depressive disorder, OCD,
panic disorder,
social anxiety disorder, GAD and
PTSD.