Botox is injected into 7 specific muscle areas around your head and neck to help prevent migraine headaches or migraine attacks before they start. Areas include the forehead, bridge of the nose, the temples, the neck, the back of the head, and just above the shoulder blades in your upper back.

Botox was introduced for treatment of chronic migraine in 2000, after some people receiving injections for cosmetic treatment of facial lines reported improvement of headaches. Initial studies after that observation produced conflicting results.

When given by an experienced and qualified health care specialist, botulinum toxin injections are relatively safe. However, some people experience pain, bruising or swelling where the drug was injected. Other possible side effects are: Headache or flulike symptoms.

Botox aims to reduce how often you have migraine attacks and how severe they are. Most people have at least two treatment cycles before deciding if Botox is effective. A good response to Botox is usually a 30-50% reduction in how many headaches you have.

Key Points. The recommended total dose of Botox (onabotulinumtoxinA) for chronic migraine prevention is 155 Units administered into a muscle (intramuscularly). This is given as 0.1 mL (5 Units) injections divided across 7 specific head and neck muscle areas, for a total of 31 individual injections per session.

The only difference between the two procedures is that with Botox for migraines, they may do a few more shots in areas where the pain is experienced.

Botulinum toxin interferes with the transmission of these substances, typically where the nerves and muscles meet. Researchers think that when the drug is injected into the muscles around the face, head and neck, it is taken up by the nerves and interferes with pain-associated neurotransmission.

Results can last for 10 to 12 weeks, or sometimes longer. Most people receive Botox® treatments every three months for a year or more, until their migraine symptoms ease. For some people, migraines may go away completely over time.

Possible side effects and unwanted results include: Pain, swelling or bruising at the injection site. Headache or flu-like symptoms. Droopy eyelids or crooked eyebrows.

Other side effects of BOTOX include dry mouth; discomfort or pain at the injection site; tiredness; headache; neck pain; eye problems such as double vision, blurred vision, decreased eyesight, drooping eyelids, swelling of your eyelids, and dry eyes; drooping eyebrows; and upper respiratory tract infection.

Botox Treatment You'll get several shots of Botox around your head and neck once every 12 weeks to dull or prevent migraine headaches. You may need 30 to 40 shots in all, and you'll get an equal number on each side of your head.

Botox for chronic migraine consists of 31 injections in the head and neck every 12 weeks. Injection sites include the forehead, temples, back of the head, upper neck, and shoulders. Each treatment takes less than 10 minutes, and the injections are generally well tolerated.