Common questions about topiramate

Topiramate works by reducing the spread of seizure activity in the brain and restoring the normal balance of nerve activity.

For epilepsy, brain cells normally talk to each other using electrical signals and chemicals. Seizures can happen when the brain cells are not working properly or working faster than normal. Topiramate slows down these electrical signals to stop seizures.

For migraines, we do not fully understand how topiramate works. It's thought that it calms overactive nerve cells in the brain that cause migraines.

For epilepsy, it can take 2 to 4 weeks for topiramate to work fully.

For migraines, it can take 1 month for migraine attacks to be less frequent.

But it can take 2 to 3 months for topiramate to work fully for migraines.

There do not seem to be any long-term side effects from topiramate. Many people take it safely for many months or years.

There are lots of other medicines that can be used for epilepsy, but they work in different ways.

They might have different side effects, or be taken more or less often. The choice of medicine will depend on the type of seizures that you have. Your doctor will discuss the best medicine with you.

Other epilepsy medicines include:

• carbamazepine
• clobazam
• ethosuximide
• gabapentin
• lamotrigine
• levetiracetam
• pregabalin
• sodium valproate
• valproic acid

To help to decide, your doctor will take into account your age and sex, the medicines you're already taking and any other health problems you have.

It's usual to try to treat epilepsy using a single medicine. If this medicine is not working well or you're getting side effects, your doctor will generally try you on a different one.

If a single medicine is not preventing your seizures, your doctor may recommend taking 2 or more epilepsy medicines at the same time.

If topiramate is giving you side effects or you're worried it's not working for you, ask your doctor or specialist to recommend a different medicine.

There are lots of other medicines that can be used to prevent migraines, but they work in different ways.

They might have different side effects, or be taken more or less often.

They include:

• beta blockers, such as propranolol
• antidepressants, such as amitriptyline
• other epilepsy medicines, such as sodium valproate

It's not possible to say that one works better than the others.

The choice will normally depend on your age, sex, any other health conditions and how your other medicines have worked for you in the past.

If you want to switch medicines, it's very important to follow your doctor's advice.

Switching from topiramate to a different medicine will be different for each person.

If you want to switch, you'll usually start taking the new one at a low dose and slowly build up the dose while you're still taking topiramate.

Once you're taking the correct dose of the new medicine, you should be able to slowly reduce your dose of topiramate.

It can take several weeks or months until you have stopped taking topiramate completely.

Do not stop taking topiramate suddenly unless your doctor tells you to.

If you're taking it to prevent migraines, your condition could get worse for a short time after you stop taking it.

If you're taking topiramate for epilepsy, it's possible that you'll get seizures once you stop taking it.

You can prevent these withdrawal seizures by reducing the dose of your topiramate gradually.

You're unlikely to get any other withdrawal symptoms when you stop taking this medicine.

If you have epilepsy, you're entitled to free prescriptions for all of your medicines, not just your epilepsy ones.

To claim your free prescriptions, you'll need a medical exemption certificate.

The application form for the medical exemption certificate is called FP92A. You can get this from your doctor's surgery. You'll need to fill in the form and your doctor will sign it and send it off.

Topiramate might stop these contraceptives working:

• combined hormonal contraceptives (the combined pill, patches, and vaginal ring) – look out for bleeding between periods, which might be a sign the contraception is not working. Talk to your doctor if this happens. Your doctor may advise you to use a different type of contraceptive, or condoms as well as combined hormonal contraceptives
• progestogen-only contraceptive pill and implants – your doctor may advise you to use a different type of contraceptive
• emergency contraception – tell your pharmacist or doctor that you take topiramate if you need emergency contraception. You may need an increased dose or to use the copper coil

You can use the contraceptive injection or coil with topiramate.

If topiramate makes you have severe diarrhoea for more than 24 hours, your contraceptive pills may not protect you from pregnancy. Check the pill packet to find out what to do.

Find out more:

• what to do if you're sick or have diarrhoea when taking the combined pill
• what to do if you're sick or have diarrhoea when taking the progestogen-only pill

You may feel sleepy, tired or dizzy when you first start taking topiramate. This may also happen if your dose has increased.

If you're affected, do not drive, ride a bike or operate machinery until you feel better.

It's an offence to drive a car if your ability to drive safely is affected. It's your responsibility to decide if it's safe to drive. If you're in any doubt, do not drive.

Talk to your doctor or pharmacist if you're unsure whether it's safe for you to drive while taking topiramate. GOV.UK has more information on the law on drugs and driving.

If you have epilepsy, you're not allowed to drive until you have had no seizures for 1 year.

If you change your epilepsy medicine, your doctor will tell you whether you need to stop driving and for how long.

It's best not to drink too much alcohol while taking topiramate.

It may make you feel sleepy or tired, and alcohol and hangovers can bring on seizures in some people with epilepsy.

Apart from not drinking too much alcohol, you can eat and drink normally while taking topiramate.