Migraine is a disorder most notable for headache and aura, but gastrointestinal (GI) symptoms are prevalent—they may presage migraine (as in the case of infantile colic, cyclic vomiting syndrome [CVS], abdominal migraine [AM]), accompany acute migraine attacks, or predominate in the presentation (as in the case of CVS and AM). In addition, GI conditions, such as irritable bowel syndrome (IBS), peptic ulcer disease (PUD), celiac disease (CD), and inflammatory bowel disease are associated with migraine. Successful treatment of migraine variant syndromes, such as CVS and AM, with acute and preventive migraine therapies, and improvement of migraine with the treatment of comorbid GI conditions (e.g., IBS, PUD, and CD) supports the link between migraine and the GI system. Physiological mechanisms underpinning this link may be related to the brain-gut-microbiota axis with its bidirectional connections between the central nervous system, the gut, and the intestinal microbiota. “Dysbiosis,” a term describing negative alteration of gut-microbiota resulting in increased gut permeability, release of proinflammatory cytokines, and stimulation of nociceptive responses in the trigeminovascular pathway, has been demonstrated in migraine and its GI comorbidities.