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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 is for parents and carers about how to use this medicine in children. Our information sometimes differs from that provided by the manufacturers, because their information is usually aimed at adults. 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 medicine

Zonisamide
Brand name:
Zonegran®

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. All capsules contain gelatin. Zonegran capsules also contain soya.
  • Liquid medicine: Hospital pharmacies may be able to provide a liquid medicine that contains either 10 mg or 8 mg in 1 mL of medicine. You will need to check which strength your child is given. 

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, it may sometimes be given 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 am and 8 am and between 7 pm and 8 pm. 

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 can be taken with or without food.

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, mashed potato or jam. Make sure your child swallows it all straight away, without chewing. 

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.

If your child is sick again, seek advice from your family doctor, pharmacist or hospital. 

What if I forget to give it?

If you usually give it once a day in the evening
If you remember before bedtime, give the missed dose. You do not need to wake up a sleeping child to give a missed dose. You can give the missed dose in the morning, as long as this is at least 12 hours before the evening dose is due. 
If you usually give it twice a day
If you remember up to 4 hours after you should have given a  dose, give your child the missed dose. For example, if you usually give a dose at about 7am, you can give the missed dose at any time up to 11 am. If you remember after that time, do not give the missed dose. Just give the next dose as usual

Never give a double dose of zonisamide.

What if I give too much?

It can be dangerous to give your child too much zonisamide

If you think you may have given your child too much zonisamide, contact your doctor or local NHS services services (see details at end of leaflet) 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

If your child is short of breath or is wheezing, or their face, lips or tongue start to swell, or they develop a rash, they may be allergic to zonisamide. Take your child to hospital or call an ambulance straight away.

If your child has a rash and is also generally unwell and has a fever (high temperature) or unusual bruises or bleeding, contact your doctor or take your child to hospital straight away, as this may indicate a more serious reaction.

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 pains 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 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.
  • It is important to check with your doctor or pharmacist before giving any other medicines to your child. This includes herbal and complementary medicines and medicines that contain cannabidiol (cannabis). 
  • Zonisamide should not be taken with some medicines. It is important to tell your doctor and pharmacist about any other medicines your child is taking before starting zonisamide.

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 contraception to prevent 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 or epilepsy nurse 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  ‘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. Liquid medicines may need to be kept in the fridge. Check the instructions on the bottle.
  • 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: 
Publication date: 
10/04/2019