Botox is licensed for the treatment of chronic migraine, defined as 3 months of at least 15 days of headache a month, of which at least 8 days have migrainous features, such as nausea, light or noise sensitivity, pulsating or lateralized pain.
How does it work in migraines?
It is thought that botulinum toxin gets into the small nerves that carry pain from the head to the brain, known as C-fibres. This reduces the number of chemicals released from the nerve ending and therefore interrupts the feedback pathway that perpetuates migraine and headache