Common questions about lamotrigine

Seizures are bursts of electrical activity in the brain that temporarily affect how it works. Lamotrigine slows these electrical signals down to stop seizures.

For bipolar disorder, it's not really known how lamotrigine prevents low mood. It might work in a similar way to epilepsy. Sometimes it's called a mood stabiliser, as it reduces mood swings.

It usually takes around 6 weeks for lamotrigine to work properly. This is because the dose needs to be increased slowly to prevent side effects.

You may still have seizures or feel low during this time.

Many people can take lamotrigine safely for several months or years.

But there are some side effects that might happen over a long time. There have been reports of osteoporosis and osteopenia, which increase your risk of breaking a bone.

Your doctor can arrange for tests to check your bone strength.

Regular exercise and a good diet can also help keep your bones strong.

If you're taking lamotrigine for epilepsy, stopping it suddenly can cause seizures.

Coming off lamotrigine should be done very slowly and might take a few months.

If you're taking lamotrigine for bipolar disorder, it's usually safe to stop taking it without having to reduce your dose first.

If you get a serious side effect, such as a severe skin rash, your doctor may tell you to stop taking lamotrigine straight away, even if you have epilepsy.

There are many different medicines for treating epilepsy. They work in different ways, and they might have different side effects, or be taken more or less often.

It's not possible to say that one works better than the other. It varies from person to person, and depends on the type of seizures and how often you have them. Your doctor will discuss the best medicine for you.

Other epilepsy medicines include:

• brivaracetam
• carbamazepine
• clobazam 
• ethosuximide
• gabapentin
• levetiracetam
• phenytoin
• pregabalin
• sodium valproate
• topiramate

Before prescribing a medicine, your doctor will also take into account your age and sex, the medicines you're already taking and any other health conditions 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 controlling your seizures, your doctor may recommend taking 2 or more epilepsy medicines at the same time.

If you have bipolar disorder, there are several types of medicine to prevent low mood (depression).

It's not possible to say that one works better than another as it varies from person to person.

Lithium is commonly used for treating low mood in bipolar disorder, as well as a medicine called quetiapine (an antipsychotic medicine).

You can take lamotrigine on its own, or sometimes together with lithium or quetiapine, depending on what your doctor recommends. Your doctor or specialist will find the medicines that work best for you.

If you're switching medicines, it's very important to follow your doctor's advice.

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 lamotrigine.

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

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

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 GP surgery.

You'll need to fill in the form, then your doctor will sign it and send it off.

Tell your surgeon that you take lamotrigine. Take your medicine as normal on the day of your surgery, unless your doctor or surgeon advises you not to.

Lamotrigine does not usually affect weight at all.

It's not always important to stay on the same brand.

If your epilepsy has been hard to control in the past and the brand of lamotrigine you're now taking is working well for you, your doctor may recommend you stay on the same one.

If you take lamotrigine for bipolar disorder, most people do not have to stay on the same brand.

Talk to your doctor if you have been asked to switch to a different brand of lamotrigine and you're worried about it.

The combined pill, patch and vaginal ring can lower the amount of lamotrigine in your blood, so you might want to use a different type of contraception.

If you decide to take the combined pill, you may need to change your dose of lamotrigine, but this depends on what other epilepsy medicines you're taking.

Lamotrigine might stop the combined pill working. Look out for bleeding or spotting between your periods (breakthrough bleeding), which might be a sign the pill is not working. Talk to your doctor if this happens.

You can take the progestogen-only contraceptive pill, but lamotrigine might increase the amount of progesterone in your blood and cause you to have more side effects.

Speak to your doctor if you're worried.

Lamotrigine does not affect these contraceptives:

• injection
• implant
• coil
• emergency contraception
• condoms

However, if lamotrigine makes you sick (vomit), 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 lamotrigine or the dose is increased. If this happens to you, do not drive, ride a bike or operate machinery until you feel more alert.

It can also cause blurred vision. Do not drive or ride a bike if your vision is affected.

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

You're not allowed to drive for 6 months after changing your epilepsy medicine.

Yes, you can drink alcohol with lamotrigine. But it may make you feel sleepy or tired, and alcohol and hangovers can bring on seizures in some people with epilepsy.

During the first few days of taking lamotrigine, it's best to stop drinking alcohol until you see how the medicine affects you.

If you do drink, try not to have more than the recommended guidelines of up to 14 units of alcohol a week. A standard glass of wine (175ml) is 2 units. A pint of lager or beer is usually 2 to 3 units of alcohol.

You can eat and drink normally while taking lamotrigine.