Traditional risk factors for spontaneous intracerebral hemorrhage include hypertension, cerebral amyloid angiopathy, and underlying neoplasm or vascular malformation. There have been only a handful of published case reports regarding phosphodiesterase type-5 (PDE-5) inhibitor-associated intracerebral hemorrhage.

Our patient is the first described case to have two separate intracerebral hemorrhages in the setting of tadalafil use. The effects of PDE-5 inhibitors on the intracranial vasculature are uncertain. Studies have shown that PDE-5 inhibitors may lead to an increase in cyclic guanosine monophosphate in the brain via the PDE-1 and PDE-2 enzymes, thus leading to cerebral vasodilation. PDE-5 inhibition may also lead to impairment of platelet activation and aggregation. The combined effects on cerebral blood flow and platelet activity may increase the risk of intracerebral hemorrhage. Therefore, in intracerebral hemorrhage patients, it appears sensible to avoid future use of PDE-5 inhibitors.