Optipar (Paroxetine)

Paroxetine is a selective serotonin reuptake inhibitor that acts on mood‑regulating pathways in the central nervous system.

• Major depressive disorder: alleviates depressive symptoms and improves mood.
• Generalized anxiety disorder: reduces excessive worry and anxiety.
• Social anxiety disorder: lessens fear of social situations and improves functioning.
• Panic disorder: decreases frequency and severity of panic attacks.
• Obsessive‑compulsive disorder: diminishes intrusive thoughts and compulsive behaviors.

• Paroxetine selectively inhibits the reuptake of serotonin (5‑HT) into presynaptic neurons, increasing extracellular serotonin levels and enhancing serotonergic neurotransmission throughout the brain, which contributes to mood stabilization and anxiety reduction.

Paroxetine may cause a range of adverse reactions that vary in frequency and severity.

Common Side Effects

• Nausea
• Dry mouth
• Drowsiness
• Insomnia
• Sweating
• Sexual dysfunction

Serious or Rare Side Effects

• Suicidal thoughts or behavior
• Serotonin syndrome
• Severe allergic reactions
• Hyponatremia
• Abnormal heart rhythm
• Elevated intra‑ocular pressure

Paroxetine should be used with careful clinical oversight, particularly in populations at risk for certain adverse outcomes.

• Assess psychiatric history: screen for suicidal ideation before initiating therapy.
• Monitor for serotonin syndrome: watch for agitation, hyperthermia, and neuromuscular abnormalities.
• Evaluate hepatic function: adjust if significant liver impairment is present.
• Caution in elderly patients: increased sensitivity to side effects such as hyponatremia.
• Avoid abrupt discontinuation: taper gradually under medical supervision.
• Store at ambient temperature: keep in the original packaging, protect from moisture and direct sunlight.

Paroxetine can interact with several other medicines, altering its effectiveness or increasing the risk of adverse events.

Major Interactions (Avoid)

• Monoamine oxidase inhibitors (MAOIs): risk of serotonin syndrome.
• Pimozide: may cause serious cardiac effects.
• Thioridazine: increased risk of QT prolongation.

Moderate Interactions (Monitor Closely)

• NSAIDs and anticoagulants: heightened bleeding risk.
• CYP2D6 substrates (e.g., codeine, tramadol): altered metabolism.
• Antihistamines: may enhance drowsiness.
• Alcohol: can increase central nervous system depression.
• Herbal supplements (St. John’s wort): may reduce efficacy.