Experimental data support the concept of cavernosal damage and suggest a protective role for daily dosage of a PDE5-I ; however , similar data have not yet been replicated in humans .
Penile rehabilitation programs are common in clinical practice , but there is no definitive evidence to support their use or the best treatment strategy .
PDE5-Is are efficacious and safe in young patients with normal preoperative erectile function who have undergone bilateral nerve-sparing radical prostatectomy .
On-dem and use of a PDE5-I may be at least as efficacious as daily use .
PDE5-I use in penile rehabilitation programs is not supported by rigorous level 1 evidence -based medicine .
PDE5-Is are an efficacious and safe treatment for post-RP ED in properly selected patients .
The experimental results on the protective role of daily dosages of PDE5-Is , while robust , have not been replicated in humans .
CONTEXT  Erectile dysfunction ( ED ) after radical prostatectomy ( RP ) has a significant negative impact on a patient 's health-related quality of life .
Phosphodiesterase type 5 inhibitors ( PDE5-Is ) have recently been utilized not only as a treatment of ED in this population but also as a preventive strategy in penile rehabilitation programs .
OBJECTIVE To eluci date the pathophysiologic mechanisms of post-RP ED , to assess the need for rehabilitation following surgery , and to analyze the basic scientific evidence and clinical applications of PDE5-Is for the prevention and treatment of ED .
EVIDENCE SYNTHESIS Post-RP ED has many factors .
Cavernosal nerve injury induces pro-apoptotic factors ( ie , loss of smooth muscle ) and pro-fibrotic factors ( ie , an increase in collagen ) within the corpora cavernosa .
Efficacy, safety and patient acceptance of sildenafil citrate as treatment for erectile dysfunction.
PURPOSE We assessed the efficacy and safety of sildenafil citrate as treatment for erectile dysfunction . MATERIAL S AND METHODS A total of 433 completely evaluated men with chronic erectile dysfunction were treated with sildenafil citrate . Response was assessed prospect ively by baseline and followup physician interviews , and by a patient self-administered 15-item question naire on the domains of patient treatment response and satisfaction , partner treatment satisfaction , comparative previous treatment satisfaction , adverse effects , and patient and partner quality of life . RESULTS Of the 304 men ( 70.2 % ) who completed the question naire 278 received sildenafil , including 186 who previously had undergone treatment for erectile dysfunction , principally involving intracavernous injection therapy . A response was elicited by a median dose of 100 mg . in 188 patients ( 67.6 % ) who achieved erection suitable for sexual intercourse . Those with psychogenic erectile dysfunction responded significantly better than those with organic dysfunction ( p < 0.001 ) . Erection suitable for intercourse was attained by 30.8 % of patients with erectile dysfunction after radical prostatectomy and 80 % with cavernous veno-occlusive dysfunction . Of previous intracavernous injection responders 29.9 % were refractory to sildenafil , while 33 . 3 % of previous intracavernous injection nonresponders responded to sildenafil . The sildenafil response was considered inferior to the intracavernous injection response by 43.6 % of the men who previously responded to intracavernous injection , of whom 51.5 % continued to receive intracavernous injection as the only treatment ( 19.5 % ) or as an alternative to sildenafil ( 32 % ) . Adverse effects in 53.6 % of cases were assessed as mild in 56.4 % , moderate in 38.3 % and severe in 5.3 % . Multiple adverse effects were reported by 62.4 % of patients , while 17 ( 6.1 % ) discontinued sildenafil as a direct result of intolerable adverse effects . The most common adverse effects were facial flushing in 33.5 % of cases , headaches in 23.4 % , nasal congestion in 12.6 % , dyspepsia in 10.1 % and dizziness in 10.8 % . Baseline patient and partner quality of life scores significantly improved after sildenafil treatment ( p < 0.001 ) , while significantly improved quality of life was noticed by 51.5 % and 43.1 % , respectively . CONCLUSIONS Sildenafil citrate is effective oral first line treatment for erectile dysfunction . Although more than 50 % of men reported adverse effects , most were considered mild and rarely result ed in treatment cessation . There was a trend in those on intracavernous injection who responded to sildenafil to continue intracavernous injection as the only therapy or as an alternative to sildenafil . Also , we noted that some cases refractory to sildenafil responded to intracavernous injection . These findings imply that intracavernous injection remains an effective erectile dysfunction treatment option
Experimental data support the concept of cavernosal damage and suggest a protective role for daily dosage of a PDE5-I ; however , similar data have not yet been replicated in humans .
Penile rehabilitation programs are common in clinical practice , but there is no definitive evidence to support their use or the best treatment strategy .
PDE5-Is are efficacious and safe in young patients with normal preoperative erectile function who have undergone bilateral nerve-sparing radical prostatectomy .
On-dem and use of a PDE5-I may be at least as efficacious as daily use .
PDE5-I use in penile rehabilitation programs is not supported by rigorous level 1 evidence -based medicine .
PDE5-Is are an efficacious and safe treatment for post-RP ED in properly selected patients .
The experimental results on the protective role of daily dosages of PDE5-Is , while robust , have not been replicated in humans .
CONTEXT  Erectile dysfunction ( ED ) after radical prostatectomy ( RP ) has a significant negative impact on a patient 's health-related quality of life .
Phosphodiesterase type 5 inhibitors ( PDE5-Is ) have recently been utilized not only as a treatment of ED in this population but also as a preventive strategy in penile rehabilitation programs .
OBJECTIVE To eluci date the pathophysiologic mechanisms of post-RP ED , to assess the need for rehabilitation following surgery , and to analyze the basic scientific evidence and clinical applications of PDE5-Is for the prevention and treatment of ED .
EVIDENCE SYNTHESIS Post-RP ED has many factors .
Cavernosal nerve injury induces pro-apoptotic factors ( ie , loss of smooth muscle ) and pro-fibrotic factors ( ie , an increase in collagen ) within the corpora cavernosa .