Paroxetine

Antidepressant Drug

Drug class: Selective Serotonin Reuptake Inhibitor

Paroxetine (SEROXAT)（中文：帕羅西汀）

Common Strengths of Paroxetine

Paroxetine are available in the following strengths:

• 10 mg, 20 mg, 30 mg, 40 mg tablets
• 12.5 mg, 25 mg, 37.5 mg, controlled-release tablets
• 10 mg/5 mL oral suspension
• 10 mg/mL oral drops

Drug Trade Names of Paroxetine

SEROXAT

Drug Usage

• Major depressive disorder
• Obsessive-compulsive disorder (OCD)
• Panic disorder
• Social anxiety disorder
• Generalized anxiety disorder
• Post-traumatic stress disorder (PTSD)

Mechanism of Action

Paroxetine is a selective serotonin reuptake inhibitor (SSRI). It works by increasing serotonin levels in the brain by inhibiting its reuptake into presynaptic neurons, thereby enhancing serotonergic acitivity.

Route of Administration

Oral

Dosages

• Depression: 20 mg/day initially, may increase to 50 mg/day maximum
• Obsessive-compulsive disoreder (OCD): 20 mg/day initially, may increase to 60 mg/ day maximum
• Panic disorder: 10 mg/day initially, may increase to 60 mg/day maximum
• Social anxiety disorder, generalized anxiety disorder, Post-traumatic stress disorder (PTSD): 20 mg/day initially, may increase to 50 mg/day maximum

Renal dose based on eGFR:

• For severe renal impairment (eGFR ≥ 30 mL/min):
  • Immediate-release tablets: 10 mg/day initially, may titrate up to 40 mg/day maximum
  • Controlled-release tablets: 12.5 mg/day initially, may titrate up to 50 mg/day maximum

Side Effects

Frequency	Adverse reactions
Common	These side effects are generally mild and often subside as the body adjusts to the medication.
	Nausea: Often mitigated by taking the medication with food
	Headaches: Drinking plenty of fluids and resting can help; avoid excessive alcohol consumption
	Insomnia: Taking fluoxetine in the morning may reduce sleep disturbances
	Fatigue or Weakness: Resting and avoiding activities that require alertness, such as driving
	Sexual Dysfunction: This includes decreased libido and difficulty achieving orgasm
	Constipation or diarrhea
	Dry Mouth: Using sugar-free gum or candy can help alleviate dry mouth
	Dizziness: Moving slowly when changing positions can help reduce dizziness
	Sweating
	Anxiety
	Tremor/shaking
Serious	Serious side effect are less common but require immediate medical attention.
	Suicidal Thoughts or Actions: especially in the first few months of treatment or when the dose is changed. Symptoms include new or worsening depression, anxiety, or unusual changes in mood or behavior.
	Serotonin Syndrome: This potentially life-threatening condition can occur when there is too much serotonin in the body. Symptoms include agitation, hallucinations, rapid heart rate, fever, nausea, vomiting, diarrhea, and muscle twitching.
	Severe Allergic Reactons: These include symptoms like difficulty breathing, swelling of the face, lips, tongue, or throat, and severe rash or hives.
	Abnormal Bleeding: Can manifest as unusual bruising or bleeding.
	Low Sodium Levels: Particularly in older adults, symptoms include headache, confusion, weakness, and difficulty concentrating.
	Mania: Symptoms include excessively high energy, severe trouble sleeping, racing thoughts, reckless behavior, and unusually grand ideas
	Seizures
	Angle-closure glaucoma (eye pain, vision changes)
	Bone fractures (increased riks)
	QT interval prolongation may lead to heart arrhythmias
	Discontinuation syndrome if stopped abruptly