How does it work?
Vimpat tablets, syrup and infusion all contain the active ingredient lacosamide, which is a medicine that is used to treat epilepsy. It works by stabilising electrical activity in the brain.
The brain and nerves are made up of many nerve cells that communicate with each other through electrical signals. These signals must be carefully regulated for the brain and nerves to function properly. When abnormally rapid and repetitive electrical signals are released in the brain, the brain becomes over-stimulated and normal function is disturbed. This results in fits or seizures.
It is not fully understood how lacosamide works to control seizures, but its mechanism appears to be different from other antiepileptic medicines.
One of the ways in which it is thought to work is by preventing sodium from entering the nerve cells when they begin to fire rapid and repetitive electrical signals. A build up of sodium in the nerve cells is necessary for the electrical signal to build up and be passed on. Lacosamide therefore prevents the excessive electrical activity that causes fits.
Lacosamide is also known to bind with a phosphoprotein found in the nervous system, called collapsin response mediator protein-2 (CRMP-2). This protein is involved in the growth and development of nerve cells.
Lacosamide can be used as an add-on treatment for people whose epilepsy has not been well controlled by taking other antiepileptic medicines. It is used to prevent partial seizures, and partial seizures that spread to secondary generalised seizures.
This medicine must be administered twice a day; it can be given as a drip into a vein (intravenous infusion) when administration by mouth is not possible.
What is it used for?
- Epilepsy. Vimpat can be prescribed for adults aged 16 years and over who suffer from partial seizures, with or without secondary generalisation, that are not well controlled by other antiepileptic medicines. Vimpat is added to the existing treatment.
- This medicine may cause dizziness or blurred vision, so may reduce your ability to drive or operate machinery safely. Do not drive or operate machinery until you know how this medicine affects you and you are sure it won't affect your performance. You should also take care with general activities until you are used to the effects of the medicine, because any dizziness may increase the risk of falling or accidental injury. You should avoid drinking alcohol while taking this medicine as it may make any dizziness worse.
- If you have epilepsy it is important to take your medication regularly, as directed by your doctor, because missing doses can trigger seizures in some people. If you have trouble remembering to take your medicine you should ask your pharmacist for advice. You may find a pill reminder box helpful.
- You should not suddenly stop taking this medicine unless your doctor tells you otherwise, as suddenly stopping treatment is likely to make your seizures return. If this medicine is stopped, it should normally be done gradually, under the supervision of your specialist.
- Vimpat syrup contains food additives, E217 and E219 which act as preservatives and may cause allergic reactions.
Use with caution in
- People severe heart disease, such as a history of heart failure, heart attack or heart rhythm disorders.
- People with severely decreased kidney function.
- People with severely decreased liver function.
- Elderly people.
- Vimpat syrup contains aspartame, which is a source of phenylalanine. This may be harmful to people with an inherited disorder of protein metabolism called phenylketonuria.
- Vimpat syrup and infusion both contain sodium, which should be taken into consideration in people on a low sodium diet.
Not to be used in
- Serious defect in the heart's electrical message pathways resulting in decreased function of the heart (2nd or 3rd degree heart block).
- The manufacturer has not studied this medicine in children and adolescents under 16 years of age. It is not recommended for this age group.
- Vimpat tablets contain soya lecithin and are unsuitable for people with an allergy to peanuts or soya.
- Vimpat syrup contains sorbitol and is not suitable for people with a hereditary intolerance to fructose.
This medicine should not be used if you are allergic to one or any of its ingredients. Please inform your doctor or pharmacist if you have previously experienced such an allergy.
If you feel you have experienced an allergic reaction, stop using this medicine and inform your doctor or pharmacist immediately.
Pregnancy and breastfeeding
Certain medicines should not be used during pregnancy or breastfeeding. However, other medicines may be safely used in pregnancy or breastfeeding providing the benefits to the mother outweigh the risks to the unborn baby. Always inform your doctor if you are pregnant or planning a pregnancy, before using any medicine.
- It is very important for women with epilepsy to talk to the doctor responsible for their epilepsy treatment before becoming pregnant. Antiepileptic medicines in general are associated with an increased risk of developmental disorders and malformations in the baby. However, stopping antiepileptic treatment during pregnancy runs the risk of the mother having seizures, which can harm both the mother and the foetus. This risk may be higher than that from continuing the medication. It is important that all the risks and benefits of treatment are weighed up. Seek medical advice from your doctor.
- The safety of lacosamide during pregnancy has not been specifically studied and its potential risk is unknown. As a result, it should only be continued during pregnancy if your doctor considers that the potential benefits clearly outweigh any potential risks to the developing baby.
- It is not known if this medicine passes into breast milk. The manufacturer advises that women who need to take this medicine should not breastfeed. Seek medical advice from your doctor.
Medicines and their possible side effects can affect individual people in different ways. The following are some of the side effects that are known to be associated with this medicine. Just because a side effect is stated here does not mean that all people using this medicine will experience that or any side effect.
Very common (affect more than 1 in 10 people)
- Double vision.
- Feeling sick (nausea).
Common (affect between 1 in 10 and 1 in 100 people)
- Blurred vision.
- Rapid involuntary movements of the eyes (nystagmus).
- Memory difficulties.
- Trouble thinking or finding words.
- Sleepiness (somnolence).
- Feeling weak or fatigued.
- Disturbances of the gut, such vomiting, constipation, flatulence.
- Problems with coordination.
- Difficulty in walking, risk of falling over.
- Sensation of spinning (vertigo) and balance problems.
Uncommon (affect between 1 in 100 and 1 in 1000 people)
- Slowed conduction of electrical messages between the chambers of the heart (first degree atrioventricular block).
- Fainting (syncope).
- Slower than normal heart beat (bradycardia).
The side effects listed above may not include all of the side effects reported by the medicine's manufacturer.
For more information about any other possible risks associated with this medicine, please read the information provided with the medicine or consult your doctor or pharmacist.
How can this medicine affect other medicines?
It is important to tell your doctor or pharmacist what medicines you are already taking, including those bought without a prescription and herbal medicines, before you start treatment with this medicine. Similarly, check with your doctor or pharmacist before taking any new medicines while taking this one, to ensure that the combination is safe.
This medicine should be used with caution in people taking other medicines that can cause an abnormal heart rhythm, seen on an ECG (electrocardiogram) as an ‘increased PR interval’. These include the following medicines:
- certain medicines for irregular heartbeats (class I antiarrhythmic drugs) such as lidocaine or flecainide
The amount of lacosamide in the blood may be decreased by the antibiotic rifampicin and by the herbal remedy St John’s wort (Hypericum perforatum). These medicines could therefore potentially make this medicine less effective and increase the risk of seizures. You should be closely monitored by your doctor if you are prescribed a course of rifampicin while taking lacosamide. You should avoid taking St John’s wort in combination with lacosamide unless it is on the advice of your doctor.
This medicine does not affect hormonal contraceptives such as the pill.
Other medicines containing the same active ingredient
There are currently no other medicines available in the UK that contain lacosamide as the active ingredient.