Lamotrigine belongs to a group of medicines called anti-epilepsy medicines, which are used to treat a number of different types of seizures (convulsions or fits) including generalised tonic-clonic seizures. This information from Great Ormond Street Hospital (GOSH) explains about lamotrigine, how it is given and some of its possible side effects.

Lamotrigine is also available under the following brand name: Lamictal®. Lamotrigine can be used on its own to treat adults and children aged 12 years or older. It can also be used in combination with other anti-epilepsy medicines in both adults and children aged two years or older. It is available as tablets and dispersible tablets in various strengths.

How is it given?

  • Lamotrigine is usually given twice a day: once in the morning and once in the late afternoon or early evening.
  • The tablets should be taken with water and swallowed whole, not chewed. The dispersible tablets can either be chewed or dispersed in two tablespoons of water or juice.
  • Lamotrigine will be prescribed in increasing doses according to your child’s weight, so it will be very specific to them. It is important that you do not give them more than the prescribed amount either as a single dose or in a 24-hour period.
  • The correct dose is when your child’s seizures are well controlled with few or no side effects.
  • Do not stop taking the medicine without consulting your doctor.

Are there any side effects?

Each person reacts differently to medicines and so your child will not necessarily suffer from every side effect mentioned. If you are concerned, please ask your doctor, nurse or pharmacist. In general, lamotrigine appears to be very effective in controlling epileptic seizures in many patients, and apart from possible skin rash, it is considered to be safe and free from serious side effects. 

The most common side effect is a skin rash that occurs in one in 10 people taking lamotrigine during the first eight weeks of treatment. Sometimes a serious rash can develop. This occurs in one in every 300 children under 12 taking lamotrigine and in one in every 1,000 children over 12 and adults. The rash is more likely to develop if your child is also taking sodium valproate, another anti-epileptic medicine. This is less likely to happen if the medicines are introduced and increased slowly. The rash usually develops within eight weeks of starting treatment, and can affect the body, face, or mouth where blisters may occur.

A high temperature and a feeling of being generally unwell may also develop alongside the rash. In a small number of cases, the rash and general illness may be severe, but this generally improves when lamotrigine is stopped. If your child develops a rash, please tell your doctor immediately, but do not stop taking the medicine unless advised to do so.

A rare side effect is drowsiness. If a child becomes drowsy it is usually when the medicine is first started. If your child is excessively tired or drowsy, please tell your doctor.

Another uncommon side effect is dizziness or tremor (shakiness). If this happens, it is also usually when the medicine is first started. However, it can develop later if the dosage is too high for your child, and blurred vision may develop alongside the dizziness. If your child develops dizziness, please tell your doctor. 

Other rare side effects include blurring or double vision or an upset stomach. 

Lamotrigine and other medicines

  • Paracetamol (Calpol®, Disprol® or Medinol® amongst others) and most other over-the-counter (OTC) medicines can be safely taken with lamotrigine. OTC medicines are those that can be bought without a prescription.
  • Antibiotics can be taken with lamotrigine.
  • Lamotrigine can be taken safely with other anti-epilepsy medicines.
  • There is a very important interaction between sodium valproate and lamotrigine. Sodium valproate causes the levels of lamotrigine to be much higher and so the dose of lamotrigine used with sodium valproate is much lower. Your doctor will take this into consideration and your child will be monitored closely when both medicines are used in combination.

Important information

  • Always give the medicine as prescribed by your doctor.
  • In certain circumstances, medicines may be prescribed for a child outside the age range recommended by the manufacturer. Unlicensed medicines are often used in children for a number of reasons for example limited data available for use in children.This is not necessarily hazardous but should be explained and agreed before use. Your doctor will explain this further to you.
  • Always check with your doctor or pharmacist before giving your child any other medicines, including herbal or complementary medicines.
  • If you miss a dose of the medicine and you remember up to four hours afterwards, give the forgotten dose immediately. If you remember at or near the time that the next dose is due, just give your child the usual dose.
  • If your child vomits within a short time of taking a dose and you are able to see the tablet in the vomit, then give the dose again. If you cannot see the tablet, do not give it again.
  • If your child has been taking the medicine regularly, do not stop it suddenly without advice. Your doctor may need to reduce the dose gradually.
  • If your child stops using a medicine or it passed its expiry date, please return it to your pharmacist. Do not flush it down the toilet or throw it away. 
  • Some anti-epilepsy medicines can affect how well the contraceptive pill works. Please discuss this with your doctor.
  • Some anti-epilepsy medicines can affect an unborn baby if taken during pregnancy. Please discuss this with your doctor.
  • Keep medicines in a safe place where children cannot see or reach them. 
  • Keep medicines at room temperature, away from bright light or direct sunlight, and away from heat. 
  • Always check that you have enough medicine and remember to order a new prescription in plenty of time. 
Compiled by: 
The National Centre for Young People with Epilepsy, GOSH Epilepsy Service and GOSH Pharmacy department in collaboration with the Child and Family Information Group, GOSH
Last review date: 
September 2014


Please read this information sheet from GOSH alongside the patient information leaflet (PIL) provided by the manufacturer. If you do not have a copy of the manufacturer’s patient information leaflet please talk to your pharmacist. A few products do not have a marketing authorisation (licence) as a medicine and therefore there is no PIL.

For children in particular, there may be conflicts of information between the manufacturer’s patient information leaflet (PIL) and guidance provided by GOSH and other healthcare providers. For example, some manufacturers may recommend, in the patient information leaflet, that a medicine is not given to children aged under 12 years. In most cases, this is because the manufacturer will recruit adults to clinical trials in the first instance and therefore the initial marketing authorisation (licence) only covers adults and older children.  

For new medicines, the manufacturer then has to recruit children and newborns into trials (unless the medicine is not going to be used in children and newborns) and subsequently amend the PIL with the approved information. Older medicines may have been used effectively for many years in children without problems but the manufacturer has not been required to collect data and amend the licence. This does not mean that it is unsafe for children and young people to be prescribed such a medicine ‘off-licence/off-label’. However, if you are concerned about any conflicts of information, please discuss with your doctor, nurse or pharmacist.