[Migraine and irritable bowel syndrome]

The association between migraine and functional gastrointestinal disorders has been confirmed by many clinical observations and epidemiological studies. In most patients during the attacks of migraine, apart from various neurological and vascular symptoms, gastrointestinal disturbances occur including nausea, vomiting, abdominal pain or diarrhea. Functional gastrointestinal disorders, such as irritable bowel syndrome (IBS), are reported in migraine patients in periods between the attacks as well. On the other hand 23-53% of IBS patients have frequent headaches. Migraine and IBS often coexist with fibromyalgia and other chronic pain syndromes and functional disorders. Migraine and IBS affect approximately 10-20% of the general population, usually young adults. Both diseases are more prevalent in women, perhaps due to the role of estrogen in their pathogenesis. Looking for the common pathogenetic mechanisms of IBS and migraine the role of the brain-gut axis, neuroimmune and neuroendocrine interactions are being considered. The influence of stress on symptom occurrence and severity seems to be associated with hyperactivity of the hypothalamic-pituitary-adrenal axis. The enteric nervous system as a source of numerous neurotransmitters and visceral reflexes is a plausible common pathogenic link between IBS and migraine. In particular serotonin being the main neurotransmitter of the gastrointestinal tract plays a relevant role in the pathogenesis of IBS as well as migraine. Nowadays, agonists and antagonists of serotoninergic receptors are the most efficacious drugs for IBS and migraine therapy. Some side effects of triptans, 5-HT(1B/D) agonists, used in migraine treatment may be connected with the influence of triptans on the gastrointestinal functions. A better understanding of the relationship between migraine and IBS may result in more effective treatment of both diseases.