About botulinum toxin type A

Botulinum toxin type A is a protein substance which is produced by the bacteria Clostridium botulinum. It is a neurotoxin which means that it interferes with the way nerves work. To be eligible for this treatment you must have headaches for 15 or more days each month, with migraine headaches being on at least eight of these days.

Botulinum toxin type A is thought to work in chronic migraine by relaxing muscles and by blocking the pain signals which are involved in the development of a migraine. These actions may have the effect of stopping a migraine headache from being triggered.

Botulinum toxin injections are also used for cosmetic purposes and for muscle spasms. This leaflet does not cover the use of botulinum toxin type A in these ways.

Before being treated with botulinum toxin type A

Before being treated with botulinum toxin type A for migraine, make sure your doctor or pharmacist knows:

• If you are pregnant, trying for a baby or breast-feeding.
• If you have an infection or any swelling near any of the areas that will be injected.
• If you have any muscle problems, particularly any muscle weakness.
• If you are taking other medicines, including those available to buy without a prescription, herbal and complementary medicines.
• If you have ever had an allergic reaction to this or to any other medicine.

How you will be given botulinum toxin type A

• Before starting this treatment, read the manufacturer's printed information leaflet from inside the pack.
• You will be given botulinum toxin type A by a doctor who is trained in the use of this treatment.
• It will be injected into the muscles around your head and neck in several different places.
• Your doctor may suggest that the treatment be repeated after a period of 12 weeks.

Getting the most from your treatment

• If you are having an operation or dental treatment, tell the person carrying out the treatment that you have received botulinum toxin type A.
• If you buy any medicines, check with a pharmacist that they are safe to use alongside this treatment.

Can botulinum toxin type A cause problems?

Along with their useful effects, most medicines can cause unwanted side-effects although not everyone experiences them. These usually improve as your body adjusts to the new medicine, but speak with your doctor or pharmacist if any of the following side-effects continue or become troublesome.

Important: if you experience any difficulty swallowing, speaking, or breathing, speak with your doctor immediately or go to your local accident and emergency department without delay.

If you experience any other symptoms which you think may be due to this medicine, speak with your doctor or pharmacist.

Important information about all medicines