Effect of Tadalafil on the Quality of Life and Sexual Life in Erectile Dysfunction

Inclusion Criteria: * have a history of erectile dysfunction (defined as a consistent change in the quality of erection that adversely affects the patient's satisfaction with sexual intercourse)of at least 3 months duration * have been using any oral prescription medication,but not tadalafil, for erectile dysfunction for a minimum period of 3 months before visit 1 * have responded to previous erectile dysfunction medication as assessed by the investigator Exclusion Criteria: * exhibit evidence of clinically significant hepatobiliary disease (including jaundice) at visit 1 * cardiovascular exclusion criteria: history of chronic stable angina treated with nitrates, recent acute cardiovascular events or procedures (myocardial infarction, coronary interventions, stroke, etc.), history of other serious cardiovascular events (e.g. arrhythmias, sudden cardiac arrest, congestive heart failure, etc.), systolic blood pressure \<90mmHg or diastolic blood pressure \<50mmHg at screening * receiving treatment with cancer chemotherapy