Zonisamide is a newer anticonvulsant medication used to control seizures/fits.

Zonisamide must be prescribed by a doctor. You should never give your child anyone else’s medications.

Side effects

All medications have side effects. Not everyone will experience side effects.

Below are some of the possible side effects your child may experience.

  • Rash - If your child develops a rash after starting Zonisamide, there are important features to look for such as: red eyes, red mouth or blisters around the mouth, nose and lips. If your child develops a rash or any of these signs you should contact your doctor immediately or go to the nearest Emergency Department. The medication may need to be stopped immediately under medical supervision.
  • Reduced sweating – your child may sweat less when taking Zonisamide. Be careful they do not become overheated in hot weather.
  • Kidney stones – children taking Zonisamide are more likely to develop kidney stones. You can help to prevent this by making sure your child drinks plenty of fluids, particularly water.
  • Acidosis in young infants your Doctor may order serum bicarbonate levels via a blood test to check for acidosis.
  • Nausea, anorexia, abdominal pain
  • Weight loss
  • Dizziness
  • Sleepiness / Disturbed sleep
  • Unsteadiness
  • Tingling sensation
  • Anxiety
  • Problems concentrating
  • Behaviour change  (e.g. aggression, irritability)


Your doctor will check and make sure that other drugs your child is taking are compatible with Zonisamide. This is also important if you are giving your child herbal or complementary medicines. The doctor can check to make sure they are compatible.

  • There are some drugs such as Sodium Valproate, Carbamazepine and Phenytoin that affect the way the body processes Zonisamide and your Doctor should advise on this.
  • Other medication such as Topiramate and Acetazolamide may increase the risk of dehydration and overheating and are usually avoided.


Monitoring and Levels

Some doctors may want to monitor renal function of children taking Zonisamide.

Epilepsy and Pregnancy

  • There is currently very limited data on the safety of Zonisamide during pregnancy.
  • It is important that pregnancies are planned and that all medications including Zonisamide are discussed with your Doctor before pregnancy.
  • Effects that Zonisamide may have on the foetus should be discussed with your Doctor.
  • For further information, refer to the Contraception and Pregnancy section.



The information provided in this handout is limited and does not replace the need for a medical consultation. It is very important you speak to your doctor about all aspects of your medication including side effects when medication is first prescribed. Report any concerns to your doctor promptly.