Anxiety is one of the conditions comorbid with migraines – if you have migraines you are 2-3 times more likely to suffer from anxiety as well. The relationship is bidirectional, meaning that if you have anxiety, you are more likely to develop migraines.
Antidepressants are proven to relieve anxiety even in the absence of depression and they are a better long-term solution than anxiety drugs such as diazepam (Valium) or alprazolam (Xanax) because they are not addictive and do not lose their efficacy over time. A unique drug that is used only for anxiety and not depression and does not cause addiction, is buspirone (Buspar).
Several studies suggest that buspirone is effective for the treatment of migraines. In a 74-patient randomized, prospective, parallel group, double-blind, placebo-controlled study (the most rigorous type of study) headache frequency showed a 43% reduction in the buspirone-treated group, but only a 10% reduction in the placebo group. This effect was independent of the presence or absence of anxiety. Similarly, antidepressants prevent migraines even if the patient is not depressed.
Buspirone has a favorable side effect profile and it does not cause withdrawal symptoms, which is often a problem with other anxiety drugs and to a lesser extent, antidepressants.