Paroxetine

Paroxetine In Dogs & Cats: Uses, Dosage and Side Effects

Overview

• It blocks serotonin reuptake in the brain, resulting in antidepressive activity and a raising in motor activity thresholds.

Uses of Paroxetine

• Treatment of generalized anxiety and impulsivity in dogs.
• Treatment of urine marking in cats, especially when accompanied by overt aggression.

Dose of Paroxetine in Dogs and Cats

Dogs:

• 1–2 mg/kg p.o. q24h.

Cats:

• 0.5–1 mg/kg p.o. q24h; can be increased to 2 mg/kg p.o. q24h but close monitoring is required.

Side Effects of Paroxetine in Dogs and Cats

• lethargy, decreased appetite, and vomiting.
• Additional possible responses: trembling, restlessness, GI disturbance, paradoxical anxiety increase.
• Caution for owners: potential increase in aggression.
• Monitoring advice: track the frequency of urination in cats.

Contraindications of Paroxetine in Dogs and Cats

• Known sensitivity to paroxetine or other SSRIs, a history of seizures.
• Do not use alongside other serotonergic agents due to the risk of serotonin syndrome.

Some Notes:

• Paroxetine should not be used within 2 weeks of MAOI treatment.
• MAOIs should not be used within 6 weeks of paroxetine treatment.
• Paroxetine antagonizes the effects of anticonvulsants.
• Not recommended for epileptic patients or with agents lowering seizure threshold.
• Caution with anticoagulants due to increased risk of bleeding in tissue trauma.
• Exercise caution with aspirin or other anticoagulants.
• Generally avoid use with other serotonergic agents to prevent serotonin syndrome.
• Trazodone use with paroxetine may be considered in exceptional cases.
• Careful monitoring for signs of serotonin syndrome is necessary in such cases.
• Fluoxetine, a specific serotonin reuptake inhibitor, is approved for use in dogs, but the veterinary formulation is not currently available.
• Clomipramine, a non-specific serotonin reuptake inhibitor, is authorized and available for use in dogs.
• These alternatives may be preferable for indications, as there is no empirical evidence supporting the use of paroxetine over these agents.