Medication for adults
Treatment of epilepsy for people aged 13 and over
Most people with epilepsy take anti-epileptic drugs (AEDs) to control their seizures. But whether to take AEDs or not is a personal choice.
'Optimal therapy' is when seizures are controlled using the smallest dose of the fewest AEDs with the least side effects. AEDs work by controlling the electrical activity of the brain cells so that seizures are less likely to happen. Which AED is suitable for an individual depends on the type of seizures they have. Most people will be started on one drug, but if this doesn't control their seizures, other drugs may be tried instead, or taken in combination.
Most AEDs have a generic and brand name. It is often helpful to have exactly the same form of AED with each prescription, and you can talk to your doctor or pharmacist about this. It is also helpful to take the right dose at the right time each day for AEDs to work best. Using a drug wallet can help remind you to take your tablets.
Side effects can happen with any type of drug, including AEDs. Some side effects happen when a drug is first taken, if you are allergic to it, or if it is taken for many years. AEDs can affect, and be affected by, other drugs. Therapeutic drug monitoring can be used to help get the best seizure control, and includes looking at your seizure control, side effects and impact of any other drugs or medical conditions.
Special sedative drugs are used to treat status epilepticus - where seizures are prolonged (don't stop on their own) or repeated without recovery in between.
Whether you are currently taking AEDs or not, it is recommended that you have an epilepsy review at least once a year, with your GP or specialist, to review your epilepsy and seizures.
What is the aim of anti-epileptic drugs?
Anti-epileptic drugs (AEDs) are used to stop seizures happening. They are not used to stop seizures while they are happening and they do not cure epilepsy. Up to 70% of people with epilepsy could have their seizures controlled (stop having seizures) once the best medication is found for them.
'Optimal therapy' is when seizures are controlled using the smallest dose of the fewest AEDs, and with the least side effects. However, some people may not get complete control of their seizures, even though they have had the most suitable drug treatment for their type of seizures. In this case they may need to take more than one type of AED, while still keeping treatment as simple as possible. This reduces the chances of possible side effects and helps people to take their medication as prescribed.
How do AEDs work?
AEDs make the brain less likely to have seizures by reducing the excessive electrical activity (or excitability) of the neurones (nerve cells) that normally cause a seizure.
Different AEDs work in different ways, but they all aim to stop seizures happening.
Starting AEDs
Before starting on AEDs, it is important that your neurologist finds out as much as possible about your epilepsy. This is because the AED they prescribe depends on the type(s) of seizures you have. As AEDs will need to be taken regularly, and often over a number of years, your neurologist will take into account any other medical conditions you may have and also your lifestyle.
The National Institute for Health and Clinical Excellence (NICE) recommends that people with newly diagnosed epilepsy are treated with one drug at a time. Taking one drug on its own is called monotherapy. If your medication needs to be changed, it should be done very gradually. If you still have seizures after trying two different AEDs, then your neurologist may look at your diagnosis again before suggesting any further AEDs for you to try.
AEDs are divided into two categories - first line and second line drugs. First line drugs are usually prescribed when treatment is started. If a first line drug does not stop seizures from happening, a different first line drug may be tried instead. Alternatively a second line drug may be prescribed alongside the first line drug, so you take two different types of AED each day. This is called polytherapy.
Usually AEDs are started at a low dose that will slowly be increased, if needed, until the most effective dose is found. This varies from one person to another, and is sometimes called your 'individual therapeutic concentration'. This is done by carefully monitoring your seizures and how you feel on the drug.
Suddenly stopping your AEDs can cause seizures to start again, or happen more often and last longer than before you stopped the AEDs. Also, taking extra AEDs can cause side effects. For these reasons, any changes to AEDs are best managed in discussion with your doctor.
Forms of AEDs
Most AEDs have at least two names, a generic name (for example carbamazepine) and a brand name given by the manufacturer (for example Tegretol). Some AEDs have more than one generic form and each form can have its own name.
For some AEDs, different forms of a generic drug, or different brand forms of a generic drug, can vary slightly. This may affect seizure control. For this reason it is recommended that you take the same form of drug all the time, whether it is a generic or brand form.
Currently (July 2010) if your prescription only has the generic name of the drug, a pharmacist can give you any form of that generic drug. However, if your prescription has the brand name of the drug, the pharmacist has to give you this brand. To ensure consistency of supply it may be helpful to get your prescription from the same pharmacist each time. Many pharmacists keep patient medication records and can help with queries about prescriptions. Some can also help review your medication (called a 'medicines use review'). If you are not sure if the AEDs you have been given are the same as those you normally take, you can check with the pharmacist or doctor.
Sometimes medication is labelled in a different language or has different packaging to what you are used to. Often this happens if the drug has been brought in from another country to the UK (a 'parallel import'). Some people find that parallel imports affect their seizure control. If you do not want to take medication that has been imported from outside the UK you have the right to refuse it and ask for a supply from within the UK.
Taking AEDs
Whether to start taking medication or not is a personal choice. To help you make the decision, you can discuss the possible risks and benefits of taking, or not taking, the medication with your neurologist. Whatever decision you make, if you want to discuss changing your treatment in the future, you can talk to your neurologist about this.
AEDs work best when they are taken regularly. This is because once taken, they start to be broken down and absorbed into the bloodstream, and go to the brain to start working. As time passes, the drug leaves the body, so the level of drug in the body goes down. Taking the drug regularly means that the drug is 'topped up' so their is a steadier level in the body all the time. The exact timing of doses is not usually crucial but it is recommended that you take the right dose around the same time or times each day, and that they are evenly spaced out. For most people, missing one dose on a rare occasion is unlikely to result in a seizure.
Some drugs are called chrono or retard (for example Epilim chrono or Tegretol retard). ‘Chrono’ and ‘retard’ mean
slow-release. If your drug is a slow-release form, the active ingredient is released into your digestive system more gradually than non-chrono forms of that drug. This means you don’t have to take it as often as other forms.
Some AEDs come in a number of forms: tablets, capsules, syrups, suppositories or oral solutions. There are also versions that can be added to food (such as sprinkles or granules) that can be useful for people who have difficulty swallowing tablets.
Drug wallets
Drug wallets can help you to take the right dose at the right time. They usually hold seven containers to keep medication in (one for each day of the week). Each container is divided into sections for the morning, afternoon and evening, and these can be removed if you are going out and want to take your medication with you.
Side effects and allergic reactions
All medications can cause side effects, but whether or not someone has them depends on their individual reaction to the medication. Side effects can vary from person to person, and from drug to drug. It is important to balance any side effects against the seizure control the medication gives you.
Some people have allergic reactions to their medication. This is rare but can be serious. A skin rash is often the first sign of an allergic reaction and usually happens soon after starting treatment. If you think you have an allergic reaction, contact your doctor as soon as possible.
Dose-related side effects can happen if the dose is too high. Starting medication at a low dose and increasing it slowly may avoid these side effects. Some side effects happen when starting new AEDs, and these effects normally wear off after a few days or weeks. If you have any ongoing side effects it is worth telling your doctor about them.
If drugs are taken for a long time (many years), long-term side effects may happen. Keeping the drug treatment as simple as possible may lower the risk of these effects.
Yellow Card Scheme
The Yellow Card Scheme is a way of reporting side effects to the Medicines and Healthcare products Regulatory Agency (MHRA). The MHRA are responsible for ensuring the safety of all medications licensed for use in the UK. Reporting side effects helps to identify potential problems for a medicine. You can get a Yellow Card form from your GP, pharmacy, hospital or NHS drop-in centre.
You can also fill in the form online at www.yellowcard.mhra.gov.uk (opens in a new window) or call 0808 100 3352.
AEDs and other medication
Some AEDs affect how other medications work and some other medications can affect how AEDs work. Telling your doctor about any other medication you are taking helps to avoid possible interactions (when different drugs affect each other). It can be helpful to check with a pharmacist before taking over-the-counter medications, including complementary therapies such as herbal remedies.
AEDs and alcohol
The decision to drink alcohol when taking AEDs is a personal choice. How alcohol affects AEDs depends on the individual, which AED they take and how much alcohol they drink. Some people find that if they drink too much alcohol it can trigger seizures, especially during a hangover. The patient information leaflet that should come with AEDs often has guidance on drinking alcohol, or you can talk to your doctors about this.
Monitoring AEDs
Any kind of drug treatment should be closely monitored. The aim of AED treatment is to stop seizures with the smallest dose of AEDs with least side effects.
Monitoring involves checking how often you have seizures and if you are having side effects. AED doses may be altered to ge the best seizure control possible for you.
If you have osteoporosis or a family history of osteoporosis, you may be asked to have a bone density test. Osteoporosis is where bones become fragile and are more likely to break. Some AEDs can affect bone density for some people.
Before starting AEDs you may be asked to have a blood test. The blood test looks at a number of things, for example how well your liver is working. This test may be repeated every one to two years.
What is therapeutic drug concentration monitoring (TDM)?
TDM a way of managing epilepsy treatment by measuring the amount (concentration) of the drug in the blood. This is done to try and get the best seizure control with the least side effects for each person. There are guidelines or 'reference ranges' that tell doctors the range of doses of an AED that is likely to control seizures. However, sometimes people will need doses above or below this range. This is because everyone is different in how they respond to treatment.
When is TDM used?
There are many situations when TDM can be useful in managing epilepsy. These include if the person:
- is starting a new AED while already on one;
- takes more than one AED;
- is still having seizures;
- has been seizure-free but starts to have seizures again;
- has other medical conditions or medications or has a poor liver or kidney function;
- has a learning disability and finds it hard to explain how their AED makes them feel;
- is pregnant;
- is over 60; or
- is taking the AED phenytoin (because it is unusual in how it is distributed around the body and TDM can help to check this distribution).
Currently few people have TDM as part of their epilepsy management.
For some AEDs, an alternative to testing blood levels is testing saliva levels. This can be helpful for children or people with a learning disability because it may be easier and less painful than a blood test. However, drug concentrations are harder to measure this way.
If you have any questions about TDM, you can ask your GP or neurologist.
More about TDM
Coming off AEDs
Some people may need to take AEDs for a long time, sometimes many years. However if someone has not had a seizure for two or more years then they may be able to think about withdrawing (coming off) their AEDs.
If you are thinking about withdrawing your AEDs, this is best done with advice from your neurologist. Stopping treatment can lead to seizures starting again, and sometimes they may last longer than they did before. Your neurologist can help you to plan your withdrawal and advise you on what to do if your seizures start again.
When thinking about coming off AEDs, it is important to consider the impact on your life if your seizures start again (for example the effect on work, leisure and driving).
For most people, if seizures do start again, taking the same AED straight away usually gives the same seizure control as before. Sometimes the original AED may not work as well as it did before.
Most people do not have withdrawal symptoms if a drug is withdrawn slowly. However, AEDs that might cause withdrawal symptoms include phenobarbitone, diazepam, clonazepam, clobazam and phenytoin. These symptoms may include feelings of anxiety, panic, restlessness or sweating.
Contraception, pregnancy and AEDs
Some types of contraception are less effective for women taking some AEDs. This depends on the individual, which AEDs they take and the type of contraception they use.
There is a chance that taking AEDs while pregnant may affect the developing baby. However these risks need to be carefully considered for each person and balanced against the possibility of seizures happening during pregnancy, which may also affect a developing baby or the safety of the mother.
Status epilepticus
Usually seizures stop by themselves. However, if a seizure continues for more than 30 minutes (or one seizure follows another with no recovery in between) this is known as status epilepticus or ‘status’.
Status during a tonic clonic (convulsive) seizure is a medical emergency and of status. For some people, missing doses of AEDs can trigger status.
Treatment of status
The emergency medication used for the treatment of status is usually a sedative. Sedative drugs have a calming effect on the brain and can stop a seizure. The point at which emergency medication is used depends on how long someone’s seizures usually last.
The two most commonly used emergency medications are diazepam and midazolam.
- Rectal diazepam - is given rectally (into the bottom).
- Buccal midazolam - is given into the buccal cavity (the side of the mouth between the cheek and the gum).
Because both these drugs are sedatives, they can cause breathing difficulties so the person must be closely watched until they have fully recovered.
For people who go into status, their doctor may prescribe diazepam or midazolam so that a carer can give it to them. Carers need specialist training to give emergency medication. It is important that every individual who is prescribed diazepam or midazolam has a written plan (or protocol) for their carers to use.
NSE provides emergency medication training, delivered by health professionals.
Epilepsy reviews
Epilepsy is a very individual condition and people respond differently to their treatment. NICE recommends that if you have epilepsy you should have a review of your epilepsy at least once a year, with either your GP or neurologist. This review should look at whether you are seizure-free, how well your seizures are controlled by the AEDs you are taking, any side effects you are having, and any other concerns that you may have.
Further information
People with epilepsy are entitled to free prescriptions for their AEDs and for any other prescribed medication that they take. To apply for free prescriptions fill in a FP92A form (or EC92A in Scotland, FP92W in Wales or HC11B in Northern Ireland). These forms are available from GP surgeries or pharmacies.
To donate blood, people with epilepsy must be seizure-free and off AEDs for three years.
For further information about AEDs visit the website www.medguides.medicines.org.uk
© National Society for Epilepsy
Information produced in July 2010
