Zonisamide (Zonegran®) is an anticonvulsant medication that’s used by veterinarians to treat dogs and cats that are suffering from epilepsy. It can be prescribed as a lone therapy, but it is most commonly prescribed as an add-on medication with either phenobarbital or potassium bromide, when one or the other is not delivering the desired effect.
Usually, Zonisamide is only prescribed as a lone treatment in cases where the patient is sensitive to phenobarbital or potassium bromide, or the pet’s owner doesn’t want to risk the potential side effects of those medications.
The exact means by which Zonisamide helps prevent convulsions is currently unknown, but it is believed that the medication effectively blocks calcium and sodium channels. This makes seizures less likely to occur in animals with epilepsy, and when they do occur, Zonisamide helps make them more manageable.
Precautions and Side Effects of Zonisamide
The use of Zonisamide is a controversial topic in the veterinary field. Because the medication is relatively new to veterinary use, many vets feel that the long-term effects of the medication on dogs and cats remain unknown. That said, many vets have used the medication with successful results.
Although it has been shown to be reasonably safe for canines and felines, Zonisamide does have the potential to produce certain side effects. The two most common side effects are sedation and ataxia, or a loss of muscle control. It can also cause diarrhea, vomiting, anorexia, and in rare cases, hyperthermia, skin reactions, and blood disorders.
There are some instances in which Zonisamide should not be used. For example, the medication should not be prescribed to dogs that are hypersensitive to sulfa drugs. It should also be avoided in pregnant or nursing dogs, as it can lead to birth defects.
Dosage and Administration of Zonisamide
The dosage and method of administration for Zonisamide should always be determined by your veterinarian. The prescribed dosage should be adhered to for the best possible results, as well as the pet’s safety. The average dosage for a dog with epilepsy is 8-12 mg/kg by mouth, every 8 to 12 hours. The most common formulation used for this medication is in sugar-coated oral tablet form.
Because Zonisamide tablets feature a sweet outer coating, it is very important to keep the medication out of reach of children.
Author: Giano Panzarella