Topiramate - Common brands: Topamax

What topiramate is for

Topiramate is used to treat seizures caused by epilepsy. It works by blocking the signals in your brain that can cause seizures.

It can also be used to prevent migraines, by calming the overactive nerve cells in the brain that cause them.

How to take topiramate

Topiramate comes as tablets, capsules and a liquid that you swallow.

How much you need to take depends on the type you're taking and what it's for. Your doctor will tell you when to take it and how much to take.

Your doctor may prescribe a low dose to start with and increase it over a few weeks until you reach a dose that works for you.

When taking topiramate:

• take it twice a day – try to take each dose at the same time in the morning and evening
• swallow tablets or capsules whole with a glass of water
• you can open capsules and sprinkle the medicine on a teaspoon of soft food, such as yoghurt or porridge, if you find swallowing difficult
• use the syringe or spoon that comes with the liquid medicine to help you measure the right dose

Always check the packet or leaflet that comes with your medicine. Ask a pharmacist or doctor for advice if you’re not sure how to take it or have any problems taking it.

If you miss a dose of topiramate

If you forget to take topiramate, take it as soon as you remember, unless it's nearly time for your next dose.

If it's nearly time for your next dose, skip the dose you missed and take you next dose at the usual time.

Do not take 2 doses to make up for a missed dose.

If you take too much topiramate

Taking an extra dose of topiramate is unlikely to cause problems, but it's important to get medical advice if you take too much because it can sometimes be dangerous.

How to stop taking topiramate

Keep taking topiramate for as long as your doctor advises you to.

If your doctor advises you to stop taking it, your dose will usually need to be reduced gradually. Always follow your doctor's advice.

Side effects of topiramate

Like all medicines, topiramate can cause side effects, although not everyone gets them.

Most side effects should ease after a couple of weeks as your body gets used to the medicine, but some can last longer.

Common side effects of topiramate include:

• feeling sick (nausea)
• dizziness
• tiredness
• diarrhoea
• loss of appetite or weight loss
• shaking or tremors
• low mood (depression)

If you feel tired or dizzy after taking topiramate, do not drive, ride a bike or use machinery until you no longer have these symptoms.

Serious side effects

Topiramate can sometimes cause serious side effects, although most of them are rare.

Possible serious side effects of topiramate include:

• an allergic reaction (anaphylaxis) – causing symptoms such as a swollen throat or tongue, a raised, itchy rash or difficulty breathing
• a skin reaction, such as a round, slightly raised rash (erythema multiforme), painful blisters (Stevens-Johnson syndrome), or peeling skin
• too much acid in your blood (metabolic acidosis) – causing symptoms such as feeling sleepy, losing your appetite and an irregular heartbeat

Who can and cannot take topiramate

Topiramate can be taken by most adults and children aged 2 years old and over, but it's not suitable for everyone.

For example, it may not be suitable if:

• you've ever had an allergic reaction to or serious side effect from topiramate or similar medicines
• you have kidney or liver problems
• you have eye problems, such as glaucoma
• you're pregnant or trying to get pregnant

Check the packet or leaflet that comes with your medicine to see if it's suitable for you. Speak to a pharmacist or doctor if you're not sure if you can use it.

Breastfeeding and topiramate

Tell your doctor if you're breastfeeding.

Your doctor will discuss it with you and may advise you to continue taking topiramate if the benefits to you outweigh the risks to your baby.

If you're taking topiramate while breastfeeding, speak to a healthcare professional or call NHS 111 if you have any concerns about your baby.

Pregnancy and topiramate

Tell your doctor if you're planning a pregnancy or you get pregnant while taking topiramate.

Topiramate has been linked to a risk of birth defects in babies if taken during pregnancy, so your doctor will usually change you to a different medicine.

They’ll usually only recommend continuing to take topiramate if you have epilepsy and other epilepsy medicines do not control your seizures. You may be able to take topiramate for epilepsy if the benefits outweigh the risks. Sometimes your doctor might want to switch you to a different medicine.

If you’re a woman and you need to take topiramate for epilepsy, you must use reliable contraception to avoid getting pregnant. Your doctor will give you advice about contraception and review your treatment at least once a year.

Find out more about taking topiramate during pregnancy on the Bumps (Best Use of Medicines in Pregnancy) website

Taking topiramate with other medicines, food and drink

There are some medicines, herbal remedies and supplements that may not mix well with topiramate.

These include:

• hormonal contraceptives, such as the combined pill – your doctor may recommend using another method of contraception, such as condoms
• any other medicines for epilepsy

Before you take topiramate, tell your doctor or pharmacist if you're taking any other medicines, herbal remedies, vitamins or supplements.

Food and alcohol with topiramate

You can eat as normal while taking topiramate.

It's best not to drink alcohol while taking topiramate because it may increase the risk of side effects or increase your chance of having a seizure.

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