Erectile dysfunction (ED) affects many men and, as the elderly population grows, the incidence of ED and demand for treatment will increase. Many organic and/or psychogenic factors cause or worsen ED. For healthcare providers and insurers, the treatment of ED involves direct medical costs (e.g. drug costs and physician visits). Indirectly, the effects of ED on the overall health and mental status of the patient may affect medical and societal costs.Management of ED should include alteration of modifiable risk factors (e.g. lifestyle and psychosocial factors); however, these modifications are frequently insufficient to completely reverse ED. Oral sildenafil 25 to 100mg is considered first-line direct therapy for ED and is effective in ≈70% of men with ED. A selective phosphodiesterase type 5 (PDE5) inhibitor, sildenafil improves the ability to attain and maintain erections and increases the rate of successful sexual intercourse in men with ED regardless of their age, presence of other medical conditions and concomitant antihypertensive or antidepressant medications. Sildenafil treatment may be initiated by primary care physicians instead of by specialists, which decreases costs to healthcare payors. Sildenafil treatment significantly improves quality-of-life related to sexual function and general well being; potential healthcare savings may result as these effects trickle down.Commonly reported adverse events are predominantly transient, mild and dose-related and include headache, flushing, dyspepsia, nasal congestion and abnormal vision. Concurrent administration of sildenafil and organic nitrates is contraindicated because marked hypotension may occur.Sublingual apomorphine (not currently available in the US) and vardenafil and tadalafil (PDE5 inhibitors in late stages of development) are other potential oral treatments for ED. Second-line pharmacological therapies include intracavernosal injections (alprostadil, papaverine, phentolamine and combinations of these agents) and intraurethral alprostadil. Non-pharmacological treatments include vacuum constrictor devices and, rarely, vascular surgery or penile implants.In economic models, sildenafil is cost effective compared with no treatment or papaverine/phentolamine injections. The cost-effectiveness of sildenafil compares favorably with that of accepted therapies for other medical conditions. Overall healthcare costs for health plan organizations did not increase significantly with the addition of sildenafil coverage. Seeking medical attention for ED may contribute to the early detection of serious concomitant conditions and result in long-term reductions in healthcare costs.In conclusion, sildenafil is an effective oral therapy for men with ED of various etiologies. Its efficacy in improving erectile function, ease-of-use and good tolerability profile make sildenafil first-line treatment for men with ED who do not have contraindications to its use.