Zonisamide for preventing seizures

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Zonisamide for preventing seizures

This leaflet is about the use of zonisamide to prevent epileptic seizures. (Seizures may be also called convulsions or fits.)

Information-Standard-Health & care information you can trustThis leaflet has been written specifically for parents and carers about the use of this medicine in children. The information may differ from that provided by the manufacturer. Please read this leaflet carefully. Keep it somewhere safe so that you can read it again.

Do not stop giving zonisamide suddenly, as your child may have more seizures.

Name of drug

Brand name:

Why is it important for my child to take this medicine?

It is important that your child takes zonisamide regularly so that they have fewer seizures.

What is zonisamide available as?

  • Capsules: 25 mg, 50 mg, 100 mg
  • Liquid medicine: Some hospital pharmacy departments may be able to provide a special liquid medicine (10 mg of zonisamide in 1 mL of medicine or sometimes 8 mg in 1 mL of medicine). You will need to check carefully which strength your child is prescribed.

When should I give zonisamide?

You will usually start by giving zonisamide once a day, while your child gets used to the medicine. This is usually in the evening.

When your child is used to zonisamide, you will usually give it twice a day: once in the morning and once in the evening. Ideally, these times are 10–12 hours apart, for example sometime between 7 and 8 am and between 7 and 8 pm.

Give the medicine at about the same time(s) each day so that this becomes part of your child's daily routine, which will help you remember.

How much should I give?

Your doctor will work out the amount of zonisamide (the dose) that is right for your child. The dose will be shown on the medicine label.

When you first start giving zonisamide to your child, you will give them a small amount and then increase the dose bit by bit over a few days or weeks. This helps your child to get used to the medicine. Your doctor will explain what to do.

It is important that you follow your doctor’s instructions about how much to give.

How should I give it?

Zonisamide should not be given with food, as it will not work properly. Your child can have food half an hour after taking the medicine.

Capsules should be swallowed whole with a glass of water, or juice. Your child should not chew the tablets.

To help give the medicine, you can open the capsule and sprinkle the contents into a teaspoonful of soft food such as yogurt, honey or jam. Make sure your child swallows it all straight away, without chewing. Your child should not eat any more food for at least half an hour.

Liquid medicine: Measure out the right amount using an oral syringe or medicine spoon. You can get these from your pharmacist. Do not use a kitchen teaspoon as it will not give the right amount.

When should the medicine start working?

It may take a few weeks for zonisamide to work properly, so your child may still have seizures for a while. Continue to give the medicine in the way that you have been told to by your doctor.

What if my child is sick (vomits)?

  • If your child is sick less than 30 minutes after having a dose of zonisamide, give the same dose again.
  • If your child is sick more than 30 minutes after having a dose of zonisamide, you do not need to give them another dose. Wait until the next normal dose.

What if I forget to give it?

  • If you remember within 4 hours, give your child the missed dose. For example, if you usually give a dose at 7 am, you can give the missed dose at any time up to 11 am. If you remember after this time, do not give the missed dose. Wait until it is time to give the next normal dose.

Never give a double dose of zonisamide.

What if I give too much?

If you think you may have given your child too much zonisamide, contact your doctor or local NHS services (111 in England and Scotland; 111 or 0845 4647 in parts of Wales) or take your child to hospital.

Take the medicine container or pack with you, even if it is empty. This will be useful to the doctor. Have the packet with you if you telephone for advice.

Are there any possible side-effects?

We use medicines to make our children better, but sometimes they cause effects that we don’t want (side-effects).

Side-effects you must do something about
  • Children may sweat less when taking zonisamide. Be careful that they don’t overheat, particularly in hot weather.
Other side-effects you need to know about
  • Your child may get stomach pain or feel sick (nausea), dizzy or drowsy (sleepy). Your child may be unsteady. Their behaviour may also change, and they may become moody or seem nervous and find it difficult to concentrate. Their sleep may be disturbed. These effects should get better as your child’s body gets used to the medicine. If they don’t, contact your doctor for advice.
  • People taking zonisamide are more likely to develop kidney stones. You can help to prevent this by making sure that your child drinks plenty of fluids, particularly water. If your child gets severe pain in their back or groin, has pain when passing urine (doing a wee), or there is blood in the urine (wee), take them to your doctor straight away.

There may, sometimes, be other side-effects that are not listed above. If you notice anything unusual and are concerned, contact your doctor. You can report any suspected side-effects to a UK safety scheme at http://www.mhra.gov.uk/yellowcard.

Can other common medicines be given at the same time as zonisamide?

  • You can give your child medicines that contain paracetamol or ibuprofen, unless your doctor has told you not to.
  • Check with your doctor or pharmacist before giving any other medicines to your child. This includes herbal or complementary medicines.

Epilepsy and pregnancy

  • Pregnancy presents a risk to both the mother with epilepsy and her unborn baby. If your daughter has sex, it is essential that she uses adequate contraception to prevent an unplanned pregnancy.
  • If your daughter is worried that she may be pregnant, it is important that she sees your family doctor as early as possible. Your daughter should keep taking her medication until she sees her doctor.

Zonisamide and pregnancy

  • Doctors don’t know yet whether zonisamide can harm an unborn baby.
  • The oral contraceptive pill can be used safely in women or girls who are taking zonisamide.

General advice about medicines for seizures

Do not suddenly stop giving any of these medicines to your child, as they may have a seizure. If you are worried, talk to your doctor but carry on giving the medicine to your child as usual.

If your child seems to have more seizures than usual, contact your doctor or epilepsy nurse.

  • If your doctor decides to stop a particular medicine, they will discuss this with you. You will usually reduce the dose bit by bit.

Do not reduce the dose without talking to your doctor first.

  • It is best that your child always has the same brand of each medicine, as there may be differences between brands. Keep a record of which medicines your child has.
  • Try to give medicines at about the same times every day, to help you remember.
  • Only give the medicine(s) to your child. Never give them to anyone else, even if their condition appears to be the same, as this could do harm.

If you think someone else may have taken the medicine by accident, contact your doctor straight away.

  • Make sure that you always have enough medicine. Order a new prescription at least 2 weeks before you will run out.
  • Make sure that the medicine you have at home has not reached the ‘best before’ or ‘use by’ date on the packaging. Give old medicines to your pharmacist to dispose of.

Where should I keep this medicine?

  • Keep the medicine in a cupboard, away from heat and direct sunlight. It does not need to be kept in the fridge.
  • Make sure that children cannot see or reach the medicine.
  • Keep the medicine in the container in which you got it.

Who to contact for more information

Your child’s doctor, pharmacist or epilepsy nurse will be able to give you more information about zonisamide and other medicines used to treat epilepsy.

You can also get useful information from: 
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