Sodium valproate for preventing seizures

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Sodium valproate for preventing seizures

This leaflet is about the use of sodium valproate to prevent epileptic seizures. (Seizures may also be called convulsions or fits.)
This 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 sodium valproate suddenly, as your child may have more seizures.

If your daughter has sex, it is essential that she uses contraception to prevent pregnancy, as sodium valproate can harm a developing baby.

Further information about sodium valproate and pregnancy can be found in the following Medicines for Children information leaflets:

• Advice tailored for girls and young women: www.medicinesforchildren.org.uk/sodium-valproate-and-pregnancy

• Advice tailored for parents and carers: www.medicinesforchildren.org.uk/sodium-valproate-and-pregnancy-information-parents-and-carers

Name of medicine

Sodium valproate (or valproic acid)
Brand names: Epilim®, Episenta®, Convulex®
Modified-release: Epilim Chrono®, Epilim Chronosphere®, Episenta®, Epival®

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

It is important that your child takes sodium valproate regularly so that they have fewer seizures (also called convulsions or fits).

What is sodium valproate available as?

Tablets: 200 mg, 500 mg
Crushable tablets: 100 mg
Modified-release tablets: 200 mg, 300 mg, 500 mg
Capsules: 150 mg, 300 mg, 500 mg
Modified-release capsules: 150 mg, 300 mg,
Modified-release granules: 50 mg, 100 mg, 250 mg, 500 mg, 750 mg, 1 g
Liquid medicine: 200 mg in 5 mL; this may contain a small amount of sugar.

When should I give sodium valproate?

Liquid, tablets and capsules that are not modified release

These are usually given twice each day: once in the morning and once in the evening. Ideally these times are 10-12 hours apart, for example some time between 7 am and 8 am, and between 7 pm and 8 pm.

Modified-release tablets, capsules and granules

(Epilim Chrono and Epival tablets, Episenta capsules, Episenta and Epilim Chronosphere granules). These are usually given once each day. This is usually in the evening unless your doctor has told you to give it in the morning. These may sometimes be given twice a day.

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 to remember.

How much should I give?

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

Your doctor will start your child on a low dose and then gradually increase it over a few days or weeks as your child gets used to the medicine and depending on how they respond. If you are not sure how much to give, check with your doctor, epilepsy nurse or pharmacist..

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

How should I give it?

Tablets: These tablets must be swallowed whole with a glass of water, juice or squash. Do not crush these tablets.

Crushable tablets: Crush the tablet and mix it with a small amount of soft food such as yogurt or a small cold drink. Your child should swallow it all straight away, without chewing.

Episenta capsules can be opened and the contents (granules) mixed with a small amount of soft food such as yogurt or jam or a small glass of water or squash. Do not crush the granules. Make sure your child swallows it all straight away, without chewing.

All other capsules should be swallowed whole with a glass of water, juice or squash. Your child should not chew the capsules.

Granules: Sprinkle or stir the granules into a small amount of soft food such as yogurt or a small cold drink. Your child should then swallow it all straight away, without chewing.

Liquid or syrup: 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 sodium valproate 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.

What if my child is sick (vomits)?

  • If your child is sick less than 30 minutes after having a dose of sodium valproate, give them the same dose again.
  • If your child is sick more than 30 minutes after having a dose of sodium valproate, 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 doctor, pharmacist or hospital. 

What if I forget to give it?

If you usually give it once a day: Give the missed dose when you remember during the day, as long as this is at least 12 hours before the next 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 7 am, 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 sodium valproate.

What if I give too much?

If you think you may have given your child too much sodium valproate, contact your doctor or local NHS services (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 help our children, but sometimes they cause effects that we don’t want (side-effects).

Side-effects that you must do something about

If your child gets bad stomach pains or starts being sick (vomits) often, or both, take them to your doctor or hospital straight away. Your child may have a serious problem called pancreatitis.

Children occasionally get serious liver disease when taking sodium valproate. If your child starts being sick every few hours, has stomach pains, is very sleepy, gets jaundice (the skin or eyes look yellowy) or has more seizures than usual, take them to your doctor or hospital straight away.

  • Your child’s hands may shake. Contact your doctor if this happens.
  • If you notice any unusual bleeding or bruising, contact your doctor.

Other side-effects you need to know about

Your child may get these side-effects when they first start taking sodium valproate. They will usually settle down within a week or so as their body gets used to the medicine. If you are concerned contact your doctor but continue to give sodium valproate to your child as usual.

  • Your child may be unusually sleepy, or their behaviour may change.
  • Your child may be hungrier than usual – this effect can last for many months. Encourage your child to eat food that is low in fat and sugar, so that they don't put on weight.
  • Your child may feel less hungry (lose their appetite), and feel sick (nausea) or be sick (vomit). This should get better after a week or so.
  • Your child may lose some hair. It will grow back, but it may be slightly curlier and darker than before.

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 www.mhra.gov.uk/yellowcard

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

  • 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 and complementary medicines.
  • Some other medicines used to treat epilepsy may affect how well sodium valporate works, or may cause side-effects. If you are worried about side-effects, or if your child seems to be having more seizures, contact your doctor or epilepsy nurse.

Epilepsy and pregnancy

  • Pregnancy presents a risk to both the mother with epilepsy and her unborn baby. 
  • If your daughter thinks that she may be pregnant, she should see her doctor as soon as possible but keep taking her medicine in the meantime.
Sodium valproate and pregnancy
  • Women and girls taking sodium valproate should not become pregnant, because this medicine may harm the unborn baby.
  • If your daughter is having sex, it is vital that she uses adequate contraception to prevent pregnancy. Your doctor or nurse will provide advice on the best types of contraception.

General advice about medicines for epilepsy

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.

Do not change the dose of any medicine without talking to your doctor first.

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

  • If your child seems to have more seizures than usual, contact your doctor or your epilepsy nurse.
  • If your doctor decides to stop a particular medicine, they will discuss this with you. They will usually reduce the dose gradually.
  • 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. If you have any questions or concerns, speak with your child's doctor or pharmacist.
  • 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.
  • 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. 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 it came in

Who to contact for more information

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

You can also get useful information from: 
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