Paroxetine is primarily used to treat major depression, obsessive-compulsive disorder (OCD), post-traumatic stress disorder (PTSD), panic disorder, generalized anxiety disorder (GAD), social phobia/social anxiety disorder, premenstrual dysphoric disorder (PMDD) and menopausal hot flashes. Paroxetine is the most potent and one of the most specific selective serotonin (5-hydroxytryptamine, 5-HT) reuptake inhibitors (SSRI). It also binds to the allosteric site of the serotonin transporter, similarly, but less potently than escitalopram. This activity of the drug on brain neurons is thought to be responsible for its antidepressant effects. Paroxetine inhibits the reuptake of norepinephrine more than the other SSRIs, just as sertraline inhibits the reuptake of dopamine more than the other SSRIs. Paroxetine has been shown to have antimicrobial activity against several groups of microorganisms, mainly Gram positive microorganisms.