Lamotrigine

Lamotrigine is used to treat epilepsy by preventing seizures and to control some mood disorders such as bipolar disorder. Lamotrigine blocks certain kinds of nerve activity and in this way reduces seizures and helps with mood disorders. In New Zealand, lamotrigine is available in different strength tablets (2 mg, 5 mg, 25 mg, 50 mg, 100 mg, 200 mg). 

• The dose of lamotrigine is different for different people.
• Your doctor will start you on a low dose, and increase your dose slowly over a few weeks to avoid side effects.
• Lamotrigine is usually taken once or two times a day but sometimes when starting lamotrigine it is taken every other day. 
• Always take your lamotrigine exactly as your doctor has told you. The pharmacy label on your medicine will tell you how much to take, how often to take it, and any special instructions.

• Swallow your lamotrigine tablets with a glass of water, milk or juice.
• If you have swallowing problems, you can chew the tablets or put the tablet in a small amount of water or fruit juice and mix well so it dissolves. This may take a few minutes. Then swallow all of the solution straight away.
• Take lamotrigine at the same times each day, to help you to remember to take it. 
• You can take lamotrigine with or without food.
• If you forget to take your dose, take it as soon as you remember; do not take double the dose.
  • If you are taking lamotrigine once every other day: take your missed dose as soon as you remember, as long as it is at least 12 hours before the next dose is due.
  • If you are taking lamotrigine once a day: take your missed dose as soon as you remember, if it is at least 12 hours before the next dose is due.
  • If you are taking lamotrigine two times a day: take it as soon as you remember if it is within 4 hours of when your dose was due. But, if it is more than 4 hours since the dose was due, just take the next dose at the right time. Do not take double the dose
• Keep taking lamotrigine every day (see tips to help you remember to take your medicines regularly. It may take a few weeks before you notice the full benefits of lamotrigine. Do not stop taking lamotrigine suddenly, especially if you are taking it for epilepsy; speak to your doctor or nurse before stopping.

• Are you pregnant or trying for a baby?
• Are you breastfeeding?
• Do you have any problems with the way your kidneys or liver work?
• Do you have Parkinson's disease?

If so, it’s important that you tell your doctor before you start lamotrigine. Sometimes a medicine isn’t suitable for a person with certain conditions, or it can only be used with extra care.

Like all medicines, lamotrigine can cause side effects, although not everyone gets them. Often side effects improve as your body gets used to the new medicine.

Skin rash

• Skin rash is a common side effect of lamotrigine and is most likely to happen in the first 8 weeks of treatment; let your doctor know if this happens. It can affect the body, face or mouth. Some people may also feel unwell and have a fever with the rash.
• The rash is more likely to happen if you are also taking sodium valproate or another anti-seizure medicine and if you have other allergies. It is less likely to happen if lamotrigine is started at a low dose and increased slowly.
• The rash is usually mild and goes away on its own but in some people it can become a severe skin reaction. Serious skin reactions have been reported in:
  • 1 in 500 adults taking lamotrigine for epilepsy
  • 1 in 100-300 children taking lamotrigine for epilepsy
  • 1 in 1000 people taking lamotrigine for bipolar disorder.
• The risk of severe skin reactions is higher in people who have autoimmune disorders such as rheumatoid arthritis and lupus. 
• If you get a rash, let your doctor know about this as soon as possible.

Other possible side effects

Lamotrigine interacts with some other medications and herbal supplements, so check with your doctor or pharmacist before starting lamotrigine or before starting any new medicines. This is especially important if you are taking the oral contraceptive pill (‘The pill’) or hormone replacement therapy (HRT), or other anti-seizure medicines.

Medsafe Consumer Information Sheet

Lamictal(external link)
Arrow-Lamotrigine(external link)
Logem(external link)

For children: Lamotrigine(external link) New Zealand Formulary for Children

Epilepsy | Mate hukihuki
Epilepsy and contraception
Epilepsy and pregnancy

1. Lamotrigine(external link) New Zealand Formulary Patient Information
2. Lamotrigine(external link) New Zealand Formulary for Children
3. Managing patients with neuropathic pain(external link) BPAC, May 2016
4. Bipolar disorder: identifying and supporting patients in primary care(external link) BPAC, July 2014

Control of the epilepsies(external link) NZ Formulary
Lamotrigine – safe prescribing – does the dose fit?(external link) SafeRx, NZ, 2019