Change to information about Lamotrigine (Lamictal)

July 2005

Recent research on a small group of patients has indicated that there can be an interaction between the oral contraceptive pill and lamotrigine. This interaction may have a twofold effect.

• The oral contraceptive pill may be less effective, increasing the risk of unwanted pregnancies.
• The lamotrigine may be less effective, increasing the risk of seizures.

Contraception

Women taking lamotrigine and the oral contraceptive pill may wish to discuss alternative contraception methods with their GP. They may wish to consider using some other form of contraception, such as a barrier method, to help avoid an unwanted pregnancy. They should also inform their GP if they have any breakthrough bleeding, as this could be a sign that the oral contraceptive pill is not working.

Anti-epileptic drug treatment

Women taking lamotrigine and the oral contraceptive pill may wish to make an appointment with their GP or epilepsy specialist to discuss their epilepsy treatment. They should also inform their GP of any change in their seizure pattern.

General advice

Women should continue to take their lamotrigine and their oral contraceptive pill as usual. They should not stop, reduce or increase the dosage of their lamotrigine or their oral contraceptive pill, unless advised to do so by their doctor. It is important to bear in mind that several other anti-epileptic drugs interact with the oral contraceptive pill, in that they reduce the contraceptive effect. However, as far as we are aware, lamotrigine is the only anti-epileptic drug that is affected by the oral contraceptive pill.