Headache caused by intracranial hypertension is quite different from that caused by intracranial hypotension. We report a patient presenting with alternating intracranial hypertension and intracranial hypotension during the treatment of severe headache. The severe headache and decreased visual acuity resolved with the revision of the cistoperitoneal shunt. Korean Journal of Headache 3(2):117-118, 2002