Sildenafil is an inhibitor of phosphodiesterase type-5 (PDE-5), is used for erectile dysfunction. There is not enough information about its effects on the central nervous system Headache, nasal congestion, facial flushing, nausea are the most common side effects. However, neurological complications such as third cranial nerve palsy, transient global amnesia, seizures, cerebral hemorrhage, and infarction are less commonly observed. We present a case of a 60-year-old man with acute ischaemic stroke, which we considered to be interrelated to sildenafil intake. Clinicians must be aware of the possibility of neurological side effects when the patient use sildenafil.