SSRI (Selective Serotonin Reuptake Inhibitor)
Potent serotonin reuptake inhibitor (SERT) with strong affinity for muscarinic acetylcholine receptors (anticholinergic effects), contributing to sedative and cognitive side effects.
Major depressive disorder (MDD), panic disorder, generalized anxiety disorder (GAD), social anxiety disorder (SoAD), obsessive-compulsive disorder (OCD), posttraumatic stress disorder (PTSD)
Hot flashes, premenstrual dysphoric disorder (PMDD), post-stroke depression (PSD), post-stroke affective lability, depression in Parkinson’s disease (PD), agitation and aggression in neurodevelopmental disabilities
Oral tablets, controlled-release tablets, and oral liquid solution (10 mg, 20 mg, 30 mg, 40 mg)
10–20 mg p.o. daily, titrating to 20–60 mg/day as tolerated
20–60 mg/day
Short half-life (~21 hours); metabolized primarily via CYP2D6; steady state in ~1 week
Sedation, weight gain, anticholinergic effects (dry mouth, constipation), sexual dysfunction, withdrawal symptoms with abrupt discontinuation
Serotonin syndrome, hyponatremia, increased risk of bleeding
Monitor for serotonin syndrome, suicidality, and withdrawal symptoms during discontinuation
Increased risk of suicidal thoughts and behaviors in children, adolescents, and young adults with MDD and other psychiatric disorders
Paroxetine is generally avoided in older adults and patients with cognitive impairment due to its significant anticholinergic burden, which increases the risk of falls, delirium, and cognitive worsening. It may worsen fatigue or cognitive slowing in patients with multiple sclerosis (MS) or traumatic brain injury (TBI). Paroxetine is typically not a first-line agent in elderly or medically complex patients.