Migraine attacks are often preceded by premonitory symptoms (PS) that may be triggered pharmacologically. We investigated the incidence of PS after administration of calcitonin gene-related peptide (CGRP) or pituitary adenylate cyclase-activating peptide-38 (PACAP38) in patients with migraine without aura (MO) who reported and did not report migraine-like attacks induced by these pharmacological triggers. In addition, we investigated the association between PS and familial predisposition for migraine. In our study, MO patients received continuous intravenous infusion of α-CGRP (n = 40) and PACAP38 (n = 32) for 20 minutes. Premonitory and nonheadache symptoms were recorded by a self-administered questionnaire. Information on familial predisposition was obtained by telephone interview of first-degree relatives using a validated semistructured questionnaire. Twenty-five of 40 patients (63%) developed a migraine-like attack after CGRP infusion and 23 of 32 patients (72%) developed an attack after PACAP38 infusion. Only 2 patients (9%) with a CGRP-induced migraine-like attack reported PS, whereas 11 patients (48%) reported PS after PACAP38. Patients who developed a migraine-like attack did not report more PS than did patients with no attack after CGRP (P = 0.519) or PACAP38 (P = 0.103). Additionally, we found no difference in PS between patients with familial predisposition of migraine (75%) and patients with no family predisposition (56%) (P = 0.101). In conclusion, CGRP did not induce PS, whereas PACAP38 induced PS in 48% of patients. However, CGRP and PACAP38 did not induce more PS in patients who developed an attack compared with those who did not develop an attack.