Only two cases connecting Sildenafil reception and acute memory impairment have been published. Two similar cases were observed in our clinic last year. Sildenafil is a potent inhibitor of cyclic guanosine monophosphate in the corpus cavernosum and therefore, increases the penile response to sexual stimulation and is used for erectile dysfunction. The most severe and life-threatening complications of Sildenafil are associated with combined administration with nitrates. The incidence of nonfatal myocardial infarction, stroke and death did not significantly differ between Sildenafil-treated and placebo-treated patients; therefore, Sildenafil does not appear contraindicated in subjects with ischemic heart disease (IHD). Scanty data are available regarding Sildenafil and cerebrovascular disease and there are only a few case reports regarding transient global amnesia (TGA) after Sildenafil use. Two cases of TGA are described immediately following the use of one dose of Sildenafil. The etiology of TGA is not yet completely understood but one of the hypothesizes suggests that the pathophysiology of this condition is related to intracranial vasomotor changes, especially due to venous congestion and venous ischemia of bilateral hippocampal structures. It is also well known that Sildenafil stimulates the relaxation of smooth muscle and causes vasomotor changes. Based on this report, as well as previous reports, it is suggested that a single dose of Sildenafil may stimulate TGA.