Pet Medication 101: Prozac

1. Drug Name:

fluoxetine hydrochloride

2. Brand Names:

Reconcile, Prozac, Olena, Prozep, Prozet, Zactin, Lovan, Sarafem, Selfemra

3. How Dispensed:

Prescription-only

4. Forms:

Veterinary formulation: 8mg, 16mg, 32mg, 64mg chewable tablets

Human formulations: 10mg, 20mg, 40mg, 60mg capsules; 90mg delayed-release capsules; 10mg, 15mg, 20mg, 40mg, 60mg oral tablets; 20mg/5mL oral solution

25mg and 50mg combination products containing olanzapine

5. Drug Type/Class:

Selective serotonin reuptake inhibitor (SSRI); behavior modifier

6. Uses in Dogs and Cats:

Used in dogs for separation anxiety, and in dogs and cats for aggression, generalized anxiety, compulsive behavior, and inappropriate urination.

7. How it Works:

Fluoxetine increases serotonin activity. Serotonin is a chemical that stabilizes mood, feelings of well-being and happiness, as well as aids in sleeping and digestion.

8. Side Effects and/or Signs of Overdose:

Side effects include decreased energy levels, decreased appetite, and gastrointestinal signs such as vomiting, diarrhea, and excessive salivation. Incoordination can also occur. Cat owners reported constipation and urinary retention.

Signs of overdose include excessive sedation. Very high doses can cause serotonin syndrome, a serious drug reaction that can lead to many adverse effects including diarrhea, high heart rate, high respiratory rate, hypertension, tremors, seizures, abnormally high body temperatures, and even coma or organ failure in the most severe cases.

9. Drug Interactions:

• Coadministration with other SSRIs or drugs that increase serotonin levels increase the risk of serotonin syndrome
• Chlorpheniramine
• Opiates
• Tramadol
• Trazodone
• Clomipramine
• Amphetamines
• Diazepam
• Monoamine oxidase inhibitors (selegiline, amitraz)
• Quinidine

10. Cautionary Statements:

• Fluoxetine should not be used in patients with exposure to other drugs that increase serotonin within 2 weeks
• In some rare instances, fluoxetine increases aggressive behavior so should be used with caution when initiating therapy in aggressive patients
• Full effects may take 4-8 weeks in some patients
• Fluoxetine should be tapered over 3-4 weeks and not discontinued abruptly. Gradual withdrawal is recommended to decrease unwanted symptoms such as agitation, anxiety, and confusion
• Appetite and body weight should be monitored closely
• Use with caution in patients with bleeding disorders and kidney disease

Read more:

Separation Anxiety in Cats

How to Find the Right Dog Trainer

Puppy Training Toolbox

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