The aim of the study was to ascertain the validity of a personal protocol used for the diagnostic classification of a group of 20 patients suffering from migraine without aura and with recurrent vertigo and postural disorders. A series of ten factors (anamnestic and constitutional) considered predictive of migrainous vertigo and four types of response to sensory provocation made it possible to identify two types of patients: type A, simultaneous presence of at least 5 (> or =50%) of the 10 factors considered and at least 2 (> or =50%) of the four established responses; type B, presence of fewer than five factors (< or =50%), or of more than five (> or =50%) but fewer than two (< or =50%) of the responses envisaged by the protocol. All patients underwent migraine prophylaxis for 4 months. Vertigo and postural status were evaluated using a questionnaire, i.e. the Dizziness Handicap Inventory (DHI), and a posturographic test before and after prophylaxis. The treatment was considered effective by 30% of the total group of 20 patients and by 75% of type A patients. No improvement was recorded in type B patients. Furthermore, the latter group did not show significant changes in the DHI or posturographic tests. Instead, type A patients demonstrated a statistically significant reduction in sway area and DHI score at the end of prophylaxis (P = 0.001). Research into a particular constitutional functional habitus, thus, proved useful for the diagnostic definition of migraine-associated vertigo.