Fluoxetine 

(floo-ox-e-teen)

• Description: Selective Serotonin-Reuptake Inhibitor (SSRI); Behavior-modification Drug
• Other Names forthis Medication: Prozac®, Reconcile®

When used as a behavior treatment, fluoxetine usually works best in combination with behavior modification therapy. It may take several weeks before you and your veterinarian can decide if the medicine is working as desired. May be given with or without food.

If your animal vomits or acts sick after receiving the drug on an empty stomach, try giving the next dose with food or a small treat. If vomiting continues, contact your veterinarian. Most common side effects are drowsiness (sleepiness) and reduced appetite.

Rare side effects that can be serious are seizures and aggression. Contact your veterinarian immediately if you see either of these effects.

Overdoses can be very serious; keep out of the reach of animals and children. Tell your veterinarian if your animal wore a flea and tick collar in the past two weeks; do not use flea collars while your animal is on this medication. Do not stop this medication abruptly without veterinarian’s guidance.

Uses/Indications:

Fluoxetine is a veterinary FDA-approved product labeled for treatment of canine separation anxiety in conjunction with a behavior modification plan. Fluoxetine may be beneficial for treatment of canine (and feline) aggression, stereotypic behaviors (and other compulsive behaviors), and anxiety. It may be useful for treatment of inappropriate elimination in cats.

How is this medication useful?

Veterinarians may prescribe fluoxetine for treating behavior problems such as aggression, obsessive-compulsive disorder, and anxiety in dogs, cats, and birds. It may also be useful in cats for inappropriate elimination.

The FDA has approved this drug for use in dogs for treating canine separation anxiety. The FDA allows veterinarians to prescribe and use products containing this drug in other animal species in certain situations. You and your veterinarian can discuss why this drug is the most appropriate choice.

How should this medication be given? 

For this medication to work, give it exactly as your veterinarian has prescribed. It’s a good idea to always check the prescription label to be sure you are giving the drug correctly. May be given with or without food. If your animal vomits or acts sick after receiving the drug on an empty stomach, try giving the next dose with food or a small treat.

If vomiting continues, contact your veterinarian. If you notice that your animal isn’t interested in eating, try hand-feeding foods it really likes. Often this side effect doesn’t last, but if it does, contact your veterinarian. Liquid forms of this medication must be measured carefully. Your veterinarian or pharmacist can help by providing special measuring spoons or syringes.

If you have difficulty getting your animal to take the medicine, contact your veterinarian or pharmacistfor tips to help dosing and reducing the stress of medication time.

• If you want to stop giving the medication before the prescription is completed, first contact your veterinarian. There may be an important reason to continue giving the medication until it’s gone.

Fluoxetine is usually tapered off slowly to reduce the chances of withdrawal symptoms (eg, vomiting, anxiety and shaking) occurring.

If you have any other questions about this medication, contact your veterinarian or pharmacist.

What are the side effects of this medication? 

Common but not serious side effects include:

• Drowsiness, lack of energy. Reduced appetite, vomiting, diarrhea. Shaking, shivering, tremors, restlessness, or panting.
• Excessive vocalization, including whining.
• Cats: Irritability, sleep disturbances, reduced appetite, and changes in urination and defecation habits (eg, going more or less than normal, diarrhea, color).

You don’t have to be overly concerned if you see any of these signs unless they persist or worsen. Contact your veterinarian if this happens.

Side effects that may be serious or indicate a serious problem: 

• Seizures, convulsions. Aggression (threatening behavior or actions) or extreme hyperexcitability (over excited and won’t settle down).
• If you see any of these signs, contact your veterinarian immediately.

Precautions/Warnings:

The manufacturer states that fluoxetine should not be used in dogs with epilepsy or a history of seizures and should not be given in combination with drugs that lower the seizure threshold (eg, acepromazine, chlorpromazine). NOTE: No published evidence exists to support the claim that phenothiazines alone lower the seizure threshold. It is not known if the use of fluoxetine in combination with this class of drugs may lower the seizure threshold, and SSRIs are recommended for treatment of anxiety and depression in humans with epilepsy. Fluoxetine is contraindicated in animals with a known hypersensitivity to it and in those receiving MAOIs (see Drug Interactions). The label states this drug should not be used in the treatment of aggressive dogs. Safe use has not been established in dogs younger than 6 months.

Fluoxetine should be used with caution in animals with diabetes mellitus because it may alter blood glucose levels. Doses may need to be reduced in animals with severe hepatic impairment.

Because norfluoxetine has a long half-life, tapering the drug may only be necessary when an animal has been on the drug long-term (ie, longer than 8 weeks); tapering the drug over a 3- to 5-week period has been recommended.

It is important not to confuse FLUoxetine with DULoxetine, FluVOXamine, or PARoxetine.