Zonisamide For Dogs With Epilepsy

(redirects here from zonegran)

This page contains information about zonisamide (zonegran) for dogs, including dosage guidelines, safety precautions and side effects.

Zonisamide also known as “Zonegran” is a relatively new anti-convulsant medication which prevents seizures by stabilizing electrical activity in the brain. Zonisamide has only been approved for human use since 2000 and trials on dogs are still ongoing, though research so far has shown that it is significantly effective in the treatment of refractory epilepsy in dogs decreasing the frequency of seizures by up to 50% when combined with phenobarbital. Despite this, you should take care when considering whether or not your dog really needs the drug.

Zonisamide dosage for dogs

The usual dosage of this medicine is 11 to 22 mg/lb body weight administered twice daily (12 hour intervals). Most vets choose to use the liquid formulation of the drug, often at concentrations of 10 to 40 ug/ml. Serious overdose is uncommon as side effects caused by administering amounts as high as four times the recommended dosage are relatively minor assuming it is a one off.

Is zonisamide safe for dogs?

Zonisamide is a drug which is safe for use in various animals including dogs when administered under veterinary guidance. It is best to only use zonisamide as an add-on medication, and only in cases where more common anti-convulsants such as phenobarbital and potassium bromide prove ineffective.

Safety precautions:

  • Never give zonisamide to dogs who don’t need it
  • Always consult with a vet before giving your dog zonisamide
  • Monitor your dog’s liver throughout treatment
  • Maintain vigilance after giving your dog zonisamide for the first time
  • Avoid use in pregnant or lactating pups

There are not many known side effects of zonisamide use in dogs but research is still ongoing. Because a full spectrum of side effects has not yet been established it is wise to only give your dog the drug if needed, and to carefully monitor your pet for 24 hours after administering the medication for the first time. Liver problems have been recorded as a potential risk of zonisamide and the liver appears to increase in weight when administering large amounts of the drug, for this reason regular liver screenings are recommended. Do not stop administering this medicine without tapering off.

Uses of zonisamide for dogs

Zonegran (zonisamide) is an anti-convulsant found to be effective in the treatment of:

  • Refractory epilepsy

Side effects of zonisamide use in dogs

The most common side effects include loss of coordination, sedation, vomiting and loss of appetite. Zonisamide may also cause binding of tissues to the eye in rare cases resulting in vision problems. Other less common side effects includes kidney stones, blood disorders and liver problems.

Gabapentin for dogs with seizures
Critters360 article about zonisamide