Psychogenic impotence is relatively uncommon. It is characterized objectively by the presence of good nocturnal and morning erections and negative findings from all other tests. During the interview, a history of highly variable erections that can be totally absent one day but virtually normal the next suggests a psychogenic cause. Virtually 100% of men with severe depression have erectile dysfunction (ED). Sildenafil (Viagra) works well for psychogenic ED; other treatment modalities are also effective because the tissues, nerves, hormone levels, and vasculature are normal. The authors usually recommend a full psychological evaluation in these patients so that the underlying etiology can be identified and treated appropriately rather than just treating the symptom of ED. Therefore, the authors defer treatment of the patient's ED until he has begun psychological testing and therapy for the underlying problem. Apathy Drug and/or alcohol use Problem may start after an illness or fever where to buy viagra safely canadian viagra for sale Horwitz and lead author Mark Buyyounouski, also at Fox Chase, were expected to present their team's findings at the annual meeting of the American Society for Therapeutic Radiology and Oncology, in Los Angeles.