This purpose of the study was to evaluate the earliest time to onset of action in adults with erectile dysfunction (often called impotence). In this study vardenafil has been compared to placebo. Patients were asked to fill in questionnaires and a diary in which they filled in details about attempts at sexual activity during study period. Patients received also a stopwatch to record the time of onset of erection. Stopwatch should be started immediately prior to initiating sexual activity and stopped when an erection perceived to be adequate for penetration was obtained.

Inclusion Criteria:

• Males with ED for more than 6 months according to the NIH Consensus statement(inability to attain and/or maintain penile erection sufficient for satisfactory sexual performance)
• Heterosexual relationship
• 18 years and older

Exclusion Criteria:

• Primary hypoactive sexual desire
• History of myocardial infarction, stroke or life threatening arrhythmia within the prior 6 months
• Nitrates or nitric oxide donors use
• Other exclusion criteria according to the US Product Information