Clozapine (Clozaril®)

Overview

Behavioral disorders in dogs and cats are a common cause for veterinary visits. Unacceptable or dangerous animal behavior problems are also a frequent reason for pets' euthanasia. 

Recently, veterinarians have placed greater emphasis on training and behavior modification, and specialists working in the field of animal behavior have increasingly adopted drugs used in human behavior for animal use. Clozapine is one of these drugs.

Clozapine has been used to treat aggression in dogs, and it may have other uses. Clozapine is a relatively new drug. Its potential uses, as well as its efficacy, are still being evaluated in clinical trials.

Clozapine is a neuroleptic.

Clozapine is a prescription drug and can only be obtained from a veterinarian or by prescription from a veterinarian.

This drug is not approved for use in animals by the Food and Drug Administration (FDA) but may be prescribed legally by veterinarians as an extra-label drug. 

Brand Names and Other Names

This drug is registered for use in humans only.

Human formulations: Clozaril® (Novartis) and generic equivalent

Veterinary formulations: None

Uses of Clozapine

As a high potency neuroleptic, clozapine should find some application in the treatment of affective states in dogs and possibly cats.

Currently clozapine has only been tried as a treatment for aggression in dogs, for which use it was found somewhat lacking in efficacy. It has been suggested that clozapine may be a useful treatment for self-injurious behavior in animals.

Precautions and Side Effects

The veterinary use of clozapine has not been well established and for this reason it should be regarded as an experimental drug.

Clozapine should not be used in animals with known hypersensitivity or allergy to the drug.

It should also be avoided in animals with uncontrolled epilepsy and in animals in hypovolemic shock.

Clozapine should be used with caution in animals with liver disease or heart disease, and in older patients. 

Sedation, rapid heart rate, low blood pressure (hypotension), tremor and drooling may occur after administration of clozapine.

Clozapine may interact with other medications. Consult your veterinarian to determine if other drugs your pet is receiving could interact with clozapine. Such drugs include anticholinergics and central nervous system depressants. 

How Clozapine is Supplied

Clozapine is available as 25 mg and 100 mg tablets.

Dosing Information

Medication should never be administered without first consulting your veterinarian.

Clozapine is usually dosed at about 1.5 mg per 2.2 pounds (1 kg), which is about one 25 mg tablet per 33 to 44 pounds (14 to 20 kg) body weight. The dosing frequency is unknown but should probably be in the order of 2 to 4 times daily.

The duration of administration depends on the condition being treated, response to the medication and the development of any adverse effects. Be certain to complete the prescription unless specifically directed by your veterinarian.