Paroxetine is an SSRI

Selective serotonin reuptake inhibitor

Selective serotonin re-uptake inhibitors or serotonin-specific reuptake inhibitor are a class of compounds typically used as antidepressants in the treatment of depression, anxiety disorders, and some personality disorders. The efficacy of SSRIs is disputed...

 antidepressant

Antidepressant

An antidepressant is a psychiatric medication used to alleviate mood disorders, such as major depression and dysthymia and anxiety disorders such as social anxiety disorder. According to Gelder, Mayou &*Geddes people with a depressive illness will experience a therapeutic effect to their mood;...

. Marketing of the drug began in 1992 by the pharmaceutical company SmithKline Beecham

Beecham (pharmaceutical company)

Beecham was a British pharmaceutical company. It was once a constituent of the FTSE 100 Index. Beecham, after having merged with SmithKline Beckman, merged with GlaxoWellcome to become GlaxoSmithKline .-History:...

, now GlaxoSmithKline

GlaxoSmithKline

GlaxoSmithKline plc is a global pharmaceutical, biologics, vaccines and consumer healthcare company headquartered in London, United Kingdom...

. Paroxetine is used to treat major depression, obsessive-compulsive disorder

Obsessive-compulsive disorder

Obsessive–compulsive disorder is an anxiety disorder characterized by intrusive thoughts that produce uneasiness, apprehension, fear, or worry, by repetitive behaviors aimed at reducing the associated anxiety, or by a combination of such obsessions and compulsions...

, panic disorder

Panic disorder

Panic disorder is an anxiety disorder characterized by recurring severe panic attacks. It may also include significant behavioral change lasting at least a month and of ongoing worry about the implications or concern about having other attacks. The latter are called anticipatory attacks...

, social anxiety

Social anxiety

Social anxiety is anxiety about social situations, interactions with others, and being evaluated or scrutinized by other people...

, and generalized anxiety disorder in adult outpatients.

In adults, the efficacy of paroxetine for depression is comparable to that of older tricyclic antidepressant

Tricyclic antidepressant

Tricyclic antidepressants are heterocyclic chemical compounds used primarily as antidepressants. The TCAs were first discovered in the early 1950s and were subsequently introduced later in the decade; they are named after their chemical structure, which contains three rings of atoms...

s, with fewer side effects and lower toxicity. Differences with newer antidepressants are subtler and mostly confined to side effects.