Keywords: subarachnoid hemorrhage (PubMed Search)
Subarachnoid hemorrhage: Unilateral or bilateral headache?
Pretty good evidence exists that most patients with subarachnoid hemorrhage will have a bilateral headache.
In fact, unilateral headache is helpful in the history in ruling out SAH in most cases. Presence of an unruptured aneurysm, however can be present with a unilateral headache.
J NeuroSurg 2006