Chronic cluster-like headache in a patient with a macroprolactinoma presenting with falsely low prolactin levels: bromocriptine versus cabergoline?

Cluster-like headache may be associated with pituitary tumors, mostly prolactinomas. Pituitary imaging and prolactin measurement should be assessed in patients presenting with cluster-like headaches with atypical features or unsatisfactory response to treatment. Furthermore, large pituitary adenomas with moderate increase in prolactin levels should prompt prolactin dilutions to avoid "hook effect".