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Clinical Guidelines |

Hormonal Testing and Pharmacologic Treatment of Erectile Dysfunction: A Clinical Practice Guideline From the American College of Physicians FREE

Amir Qaseem, MD, PhD, MHA; Vincenza Snow, MD; Thomas D. Denberg, MD, PhD; Donald E. Casey Jr., MD, MPH, MBA; Mary Ann Forciea, MD; Douglas K. Owens, MD, MS; Paul Shekelle, MD, PhD, Clinical Efficacy Assessment Subcommittee of the American College of Physicians
[+] Article and Author Information

This paper, written by Amir Qaseem, MD, PhD, MHA; Vincenza Snow, MD; Thomas D. Denberg, MD, PhD; Donald E. Casey Jr., MD, MPH, MBA; Mary Ann Forciea, MD; Douglas K. Owens, MD, MS; and Paul Shekelle, MD, PhD, was developed for the Clinical Efficacy Assessment Subcommittee of the American College of Physicians (ACP): Paul Shekelle, MD, PhD (Chair); Roger Chou, MD; Paul Dallas, MD; Thomas D. Denberg, MD, PhD; Mary Ann Forciea, MD; Robert H. Hopkins Jr., MD; Linda Humprey, MD, MPH; David B. Nash, MD, MBA; Douglas K. Owens, MD, MS; and Donna Sweet, MD. Approved by the ACP Board of Regents on 11 July 2009.


From the American College of Physicians and University of Pennsylvania, Philadelphia, Pennsylvania; University of Colorado, Aurora, Colorado; Atlantic Health, Morristown, New Jersey; Veterans Affairs Palo Alto Health Care System and Stanford University, Stanford, California; and Veterans Affairs Greater Los Angeles Healthcare System, Los Angeles, California.


Note: Clinical practice guidelines are “guides” only and may not apply to all patients and all clinical situations. Thus, they are not intended to override clinicians' judgment. All ACP clinical practice guidelines are considered automatically withdrawn or invalid 5 years after publication, or once an update has been issued.

Disclaimer: The authors of this article are responsible for its contents, including any clinical or treatment recommendations. No statement in this article should be construed as an official position of the Agency for Healthcare Research and Quality or the U.S. Department of Health and Human Services.

Grant Support: Financial support for the development of this guideline comes exclusively from the American College of Physicians' operating budget.

Potential Conflicts of Interest:Grants received: V. Snow (Bristol-Myers Squibb, Centers for Disease Control and Prevention, Novo Nordisk, Merck Vaccines, Boehringer Ingelheim, Wyeth, Sanofi Pasteur), P. Shekelle (Pfizer). Royalties: P. Shekelle (Up-to-Date). Any financial and nonfinancial conflict of interest of the group members were declared, discussed, and resolved.

Requests for Single Reprints: Amir Qaseem, MD, PhD, MHA, American College of Physicians, 190 N. Independence Mall West, Philadelphia, PA 19106; e-mail, aqaseem@acponline.org.

Current Author Addresses: Drs. Qaseem and Snow: American College of Physicians, 190 N. Independence Mall West, Philadelphia, PA 19106.

Dr. Denberg: 12631 East 17th Avenue, B180, Academic Office 1, Aurora, CO 80045.

Dr. Casey: 475 South Street, PO Box 1905, Morristown, NJ 07962.

Dr. Forciea: 3615 Chestnut Street, Philadelphia, PA 19104.

Dr. Owens: 117 Encina Commons, Stanford, CA 94305.

Dr. Shekelle: 1776 Main Street, Santa Monica, CA 90401.

Author Contributions: Conception and design: A. Qaseem, V. Snow, D.E. Casey Jr., D.K. Owens.

Analysis and interpretation of the data: A. Qaseem, D.E. Casey Jr., M.A. Forciea, D.K. Owens.

Drafting of the article: A. Qaseem, V. Snow, T.D. Denberg, D.E. Casey Jr., M.A. Forciea, D.K. Owens.

Critical revision of the article for important intellectual content: A. Qaseem, V. Snow, T.D. Denberg, D.E. Casey Jr., M.A. Forciea, D.K. Owens, P. Shekelle.

Final approval of the article: A. Qaseem, V. Snow, T.D. Denberg, D.E. Casey Jr., M.A. Forciea, D.K. Owens, P. Shekelle.

Statistical expertise: A. Qaseem.

Administrative, technical, or logistic support: A. Qaseem.

Collection and assembly of data: A. Qaseem.


Ann Intern Med. 2009;151(9):639-649. doi:10.7326/0003-4819-151-9-200911030-00151
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Description: The American College of Physicians developed this guideline to present the available evidence on hormonal testing in and pharmacologic management of erectile dysfunction. Current pharmacologic therapies include phosphodiesterase-5 (PDE-5) inhibitors, such as sildenafil, vardenafil, tadalafil, mirodenafil, and udenafil, and hormonal treatment.

Methods: Published literature on this topic was identified by using MEDLINE (1966 to May 2007), EMBASE (1980 to week 22 of 2007), Cochrane Central Register of Controlled Trials (second quarter of 2007), PsycINFO (1985 to June 2007), AMED (1985 to June 2007), and SCOPUS (2006). The literature search was updated by searching for articles in MEDLINE and EMBASE published between May 2007 and April 2009. Searches were limited to English-language publications. This guideline grades the evidence and recommendations by using the American College of Physicians' clinical practice guidelines grading system.

Recommendation 1: The American College of Physicians recommends that clinicians initiate therapy with a PDE-5 inhibitor in men who seek treatment for erectile dysfunction and who do not have a contraindication to PDE-5 inhibitor use (Grade: strong recommendation; high-quality evidence).

Recommendation 2: The American College of Physicians recommends that clinicians base the choice of a specific PDE-5 inhibitor on the individual preferences of men with erectile dysfunction, including ease of use, cost of medication, and adverse effects profile (Grade: weak recommendation; low-quality evidence).

Recommendation 3: The American College of Physicians does not recommend for or against routine use of hormonal blood tests or hormonal treatment in the management of patients with erectile dysfunction (Grade: insufficient evidence to determine net benefits and harms).

Erectile dysfunction (ED) is defined as the persistent inability to achieve or maintain penile erection sufficient for satisfactory sexual performance (1). Erectile dysfunction lasting for 3 months is considered a reasonable length of time to warrant evaluation and consideration of treatment. Erectile dysfunction is a common disorder of male sexual function and affects all age groups, especially people with advanced age, diabetes, vascular diseases, psychiatric disorders, and possibly hypogonadism (14). With the aging general population and increased life expectancy, combined with the high prevalence of diabetes and cardiovascular disease, the health care burden and quality-of-life issues associated with ED are projected to be substantial (5). In 1995, more than 152 million men worldwide were estimated to have experienced ED. The prevalence of ED is predicted to be approximately 322 million worldwide by 2025 (6). Estimates from the National Health and Nutrition Examination Survey suggested that the cost of treatment of ED in the United States could reach $15 billion if all affected men sought care (7).

The purpose of this guideline is to present the available evidence on the hormonal testing and pharmacologic management of ED. The target audience for this guideline is all clinicians, and the target population is all men with ED. Recommendations are based on the systematic evidence review by Tsertsvadze and colleagues (8) and the evidence report by the Agency for Healthcare Research and Quality–sponsored University of Ottawa Evidence-based Practice Center (5). Erectile dysfunction may be caused by chronic diseases, such as obesity, hypertension, dyslipidemia, and cardiovascular disease, or smoking; medications; psychosocial factors; and hormonal abnormalities. This guideline addresses only the utility of hormonal testing and treatment of ED. Such treatments as vacuum constriction devices, intraurethral suppositories, intracavernosal injections, and psychotherapy were not included in the evidence review and are not addressed in this guideline.

The databases used for the literature search included MEDLINE (1966 to May 2007), EMBASE (1980 to week 22 of 2007), Cochrane Central Register of Controlled Trials (second quarter of 2007), PsycINFO (1985 to June 2007), AMED (1985 to June 2007), and SCOPUS (2006). The literature search was limited to studies published in English. Reference lists of retrieved publications were scanned. The literature search was updated by searching for articles on MEDLINE and EMBASE published between May 2007 and April 2009.

Two persons independently reviewed abstracts and relevant full-text articles regarding study, study population, and treatment characteristics. Disagreements were discussed and resolved by consensus. The reviewers excluded reviews, pooled analysis, editorials, commentaries, and letters. To assess the relative benefits and harms of pharmacologic treatments for ED, eligible studies included randomized, controlled trials (RCTs) of pharmacologic ED treatments in men aged 18 years or older with ED. To assess the clinical value of routine hormonal blood tests in men with ED, eligible studies were those reporting prevalence of hypogonadism, hyperprolactinemia, or both in men with ED and RCTs comparing hormone treatment alone or in combination versus control in men with ED. For adverse events, data abstracted included the number of patients with any adverse event, specific adverse events, withdrawals due to adverse events, serious adverse events, and serious cardiovascular adverse events. To assess the risks for nonarteritic anterior ischemic optic neuropathy (NAION) in men receiving phosphodiesterase-5 (PDE-5) inhibitors, eligible studies included RCTs; nonrandomized, controlled trials; and observational studies. Treatments not generally prescribed by primary care physicians, such as vacuum constriction devices, intraurethral suppositories, intracavernosal injections, or psychotherapy, were considered beyond the scope of this guideline.

This guideline rates the evidence and recommendations by using the American College of Physicians' guideline grading system, which is a slightly modified version of the Grading of Recommendations, Assessment, Development, and Evaluation (GRADE) system (Table).

Table Jump PlaceholderTable.  The American College of Physicians' Guideline Grading System

The objective of this guideline is to synthesize the evidence for the following key questions:

Key question 1: What is the clinical utility of routine hormonal blood tests—testosterone and prolactin—in identifying and affecting therapeutic outcomes for treatable causes of ED?

Key question 2: What are the benefits of pharmaceutical treatments for patients with ED?

Key question 3: What are the harms of the pharmaceutical treatments for patients with ED?

Evidence was gathered from 29 studies, of which 28 reported measurement of testosterone (937) and 10 reported measurement of prolactin (910, 12, 1415, 20, 22, 2728, 38). Mean age of participants ranged from 47 to 60 years. The overall quality of evidence was rated as low because of between-study variability in study populations, varying hormone measurement methods, and prevalence rates of hormonal abnormalities.

The prevalence of low total testosterone levels (12, 23, 3435), low free testosterone levels (21, 29), and hyperprolactinemia (14, 2728) in men with ED varied widely across studies. The prevalence of low testosterone levels (defined in the studies as <288 ng/dL [<9.9 nmol/L] or <9.0 pg/mL [<31.2 pmol/L]) in men with ED varied from 12.5% to 35% (2021, 31). This variability may be due to between-study differences in study population characteristics, hormonal measurement methods, diagnostic criteria for ED or hormonal abnormalities, or a combination of these factors. Because evidence was insufficient to determine whether men with ED had a higher prevalence of hypogonadism or hyperprolactinemia than men without ED (3132), the value of routine hormonal testing for the evaluation of ED is unclear.

Oral PDE-5 Inhibitors

Evidence was gathered from 130 RCTs that evaluated oral PDE-5 inhibitors, alone or combination (72 RCTs of sildenafil [39107], 27 RCTs of vardenafil [13, 108133], 28 RCTs of tadalafil [134161], 2 RCTs of mirodenafil [156157], and 1 RCT of udenafil [162]), and 4 RCTs with head-to-head comparisons of PDE-5 inhibitors (163166). Treatment duration for most trials was 12 months, and 85% of the trials did not report treatment allocation concealment.

PDE-5 Inhibitor Versus Placebo
Successful Sexual Intercourse.

High-quality evidence from RCTs showed that PDE-5 inhibitors improved successful sexual intercourse. The weighted mean percentage of successful sexual intercourse attempts was 69% (range, 52% to 85%) for sildenafil versus 35.5% (range, 19% to 68%) for placebo (41, 4344, 4748, 57, 66, 69, 78, 8384, 90, 93, 100, 102103), 68% (range, 50% to 88%) for vardenafil versus 35% (range, 20% to 40%) for placebo (13, 108, 110, 112, 115116, 121, 123124, 126127, 130, 132), and 69% (range, 50% to 85%) for tadalafil versus 33% (range, 23% to 52%) for placebo (136137, 139141, 143144, 147, 149, 153157, 159). In trials enrolling men with a wide spectrum of diseases, corresponding values were 69% versus 36% (41, 4344, 4748, 57, 66, 69, 78, 8384, 90, 93, 100, 102103, 108), 68% versus 35% (13, 110, 112, 115116, 121, 123124, 126127, 130132), and 69% versus 33% (136137, 139141, 143144, 147, 149, 153157, 159).

Improvement in Erections.

High-quality evidence indicated that all 5 agents (sildenafil, vardenafil, tadalafil, mirodenafil, and udenafil) improved erections (range, 73% to 88%) compared with placebo (range, 26% to 32%) (13, 4043, 4749, 51, 5458, 60, 62, 64, 66, 6971, 74, 7780, 8284, 91, 95, 99100, 106, 109113, 115116, 118, 120, 122124, 130, 132, 136144, 146147, 149, 153157, 161162, 167168). Men assigned to PDE-5 inhibitors experienced improved erections compared with placebo recipients in trials limited to patients with specific medical conditions, such as diabetes (42, 5354, 58, 60, 104, 107, 109, 126127, 146, 161), depression (40, 52, 66, 91, 122), cardiovascular disease (45, 61, 64, 74, 80, 82, 95, 120, 133), prostate cancer (73, 96, 101, 111, 131, 142, 158, 169), multiple sclerosis (62, 106), colorectal cancer (71), schizophrenia (92), liver failure (63), and renal failure (89, 128).

Dose.

Improvement in erectile function was related to higher dose for sildenafil (50 mg vs. 25 mg but not 100 mg vs. 50 mg) and vardenafil (20 mg vs. 10 mg vs. 5 mg) but not tadalafil (20 mg vs. 10 mg vs. 5 mg) (53, 57, 74, 77, 109, 113114, 116, 118, 127, 161162, 167168).

PDE-5 Inhibitor Versus Non–PDE-5 Inhibitor

Sildenafil was more effective than non–PDE-5 inhibitor treatments, such as sublingual apomorphine, psychotherapy, continuous positive airway pressure, phentolamine, and alfuzosin, in improving erectile function (170174), frequency of penile penetration or erection maintenance, and percentage of successful intercourse attempts (175179).

PDE-5 Inhibitor Plus Non–PDE-5 Inhibitor Versus PDE-5 Inhibitor

Sildenafil combined with other ED therapies (such as psychotherapy, dihydroergotamine, cabergoline, atorvastatin, quinapril, and alfuzosin) resulted in greater improvements in erectile function and frequency of penile penetration or maintenance of erection than did sildenafil alone (169, 175, 179185).

PDE-5 Inhibitor Versus PDE-5 Inhibitor
Successful Sexual Intercourse.

Low-quality studies comparing tadalafil and sildenafil provided insufficient evidence to determine whether 1 treatment was more effective than the other (163).

Improvement in Erections.

Evidence from 2 low-quality RCTs comparing tadalafil and sildenafil was insufficient to determine the effectiveness of 1 drug over the other (163, 166).

Hormonal Treatments

Evidence was gathered from 15 RCTs that evaluated the efficacy of hormonal therapy (oral, intramuscular, gel, cream, or patch testosterone) on ED outcomes in hypogonadal men (186200).

Hormonal Therapy Versus Placebo
Successful Sexual Intercourse.

Low-quality evidence was insufficient to show whether testosterone was more effective than placebo (193, 200). In 1 low-quality trial, gel testosterone (50 to 100 mg) but not patch testosterone modestly improved the frequency of successful sexual intercourse compared with placebo (187).

Improvement in Erections.

Low-quality evidence was insufficient to determine whether testosterone was more effective than placebo (186, 189, 191, 193, 195, 197).

Hormonal Therapy Plus PDE-5 Inhibitor Versus PDE-5 Inhibitor
Successful Sexual Intercourse.

Low-quality evidence was insufficient to determine whether testosterone plus a PDE-5 inhibitor (sildenafil) was more effective than a PDE-5 inhibitor (sildenafil) and placebo in improving frequency or percentage of successful sexual intercourse attempts (188, 190).

Improvement in Erections.

Low-quality evidence was insufficient to determine whether testosterone plus a PDE-5 inhibitor (sildenafil) was more effective than a PDE-5 inhibitor (sildenafil) and placebo (188, 190, 194).

Oral PDE-5 Inhibitors
PDE-5 Inhibitor Versus Placebo

High-quality evidence showed that men receiving PDE-5 inhibitors are more likely to have at least 1 adverse event compared with placebo recipients. However, the incidence for more serious adverse events was less than 2%, with no difference between PDE-5 inhibitors and placebo. The most common adverse effects were headache, flushing, rhinitis, and dyspepsia. Less common adverse effects were visual disturbances, myalgia, nausea, diarrhea, vomiting, dizziness, and chest pain.

PDE-5 Inhibitor Versus Non–PDE-5 Inhibitor

Sildenafil was associated with fewer adverse events than non–PDE-5 inhibitors (170179).

PDE-5 Inhibitor Plus Non–PDE-5 Inhibitor Versus PDE-5 Inhibitor

Sildenafil was associated with fewer adverse events than PDE-5 inhibitors combined with non–PDE-5 inhibitors (169, 175, 179, 181185).

PDE-5 Inhibitor Versus PDE-5 Inhibitor

Very-low-quality evidence showed that adverse events did not statistically significantly differ among men receiving sildenafil, tadalafil, and vardenafil (163166).

NAION

Nonarteritic anterior ischemic optic neuropathy is defined as ischemic optic neuropathy in the absence of temporal arteritis and polymyalgia rheumatica, and “possible” NAION is defined as papillitis, optic neuritis, or both in the absence of temporal arteritis, polymyalgia rheumatica, and previous optic neuropathies. Very-low-quality evidence evaluating the association of NAION with the use of PDE-5 inhibitors showed that among 4 million veterans aged 50 years or older, PDE-5 inhibitors were not associated with an increased risk for NAION (absolute risk, 4.6 cases per 10 000 men per year; relative risk, 1.02 [95% CI, 0.92 to 1.12]); however, PDE-5 inhibitors were associated with an increased risk for possible NAION (absolute risk, 2.4 cases per 10 000 men per year; relative risk, 1.34 [CI, 1.17 to 1.55]) (201).

Priapism

Trials evaluated for this guideline did not report priapism. Prolonged erection and priapism were reported infrequently during postmarketing surveillance (202).

Contraindications

Concurrent use, regularly or intermittently, of nitrates in any form (for example, nitroglycerin and isosorbide dinitrate) is a contraindication for oral PDE-5 inhibitor therapy.

Hormonal Treatments
Hormonal Therapy Versus Placebo

Very-low-quality evidence showed that adverse events did not differ between oral or gel testosterone and placebo (187, 193, 200). Prostate-specific antigen levels were similar in testosterone and placebo groups in 3 trials reporting these data (189, 198199).

Hormonal Therapy Plus PDE-5 Inhibitor Versus PDE-5 Inhibitor

Low-quality evidence showed that the incidence of adverse events was low and did not differ between sildenafil alone versus sildenafil plus patch, gel, or oral testosterone (188, 190, 194). Prostate-specific antigen levels were not significantly higher in the sildenafil plus testosterone groups than the sildenafil groups in 2 trials reporting these data (190, 194).

The evidence regarding the utility of hormonal blood tests in identifying and affecting therapeutic outcomes for treatable causes of ED was inconclusive. The evidence demonstrated clinical benefit associated with the use of PDE-5 inhibitors regardless of the cause (such as diabetes, depression, or prostate cancer) or baseline severity of ED. The magnitude of benefit increased with severity of ED. Higher doses of sildenafil and vardenafil were associated with a modestly greater magnitude of benefit with respect to erectile function; however, this was not true for tadalafil. Overall, PDE-5 inhibitors were relatively well tolerated and were associated with mild or moderate adverse events. The incidence of adverse events did not significantly differ among the various PDE-5 inhibitors. Evidence was insufficient to determine whether PDE-5 inhibitors are associated with an increased risk for NAION.

The quality of reporting primary studies should be improved. Authors reporting trials in journals that publish ED-related research should consider using the CONSORT (Consolidated Standards of Reporting Trials) Statement as a reporting guide. Some studies evaluated the dose–response effect of PDE-5 inhibitors with respect to efficacy and harms; however, more high-quality studies are needed. The evidence regarding the incidence of adverse events was limited and inconclusive, and more high-quality head-to-head trials are needed to explore differences in adverse events, especially severe adverse events. The evidence regarding the utility of routine hormonal blood tests was inconclusive, given the limited number of studies and various methodological issues, and needs to be further developed.

Recommendation 1: The American College of Physicians recommends that clinicians initiate therapy with a PDE-5 inhibitor in men who seek treatment for erectile dysfunction and who do not have a contraindication to PDE-5 inhibitor use (Grade: strong recommendation; high-quality evidence).

Treatment with an oral PDE-5 inhibitor demonstrated statistically significant and clinically relevant improvements in sexual intercourse and erectile function in patients with ED. Improvement in erectile function was related to higher doses for sildenafil and vardenafil. However, higher doses were associated with a greater risk for an adverse effect. Nitrate therapy is a contraindication for treatment with oral PDE-5 inhibitors.

Recommendation 2: The American College of Physicians recommends that clinicians base the choice of a specific PDE-5 inhibitor on the individual preferences of men with erectile dysfunction, including ease of use, cost of medication, and adverse effects profile (Grade: weak recommendation; low-quality evidence).

The evidence is insufficient to compare the efficacy and adverse effects of different PDE-5 inhibitors for the treatment of ED because only few head-to-head trials are available. Therefore, individual preferences, ease of use, and cost of medication are reasonable criteria to help select a treatment.

Recommendation 3: The American College of Physicians does not recommend for or against routine use of hormonal blood tests or hormonal treatment in the management of patients with erectile dysfunction (Grade: insufficient evidence to determine net benefits and harms).

The prevalence of low testosterone varies from 12.5% to 36% in studies of men with ED. However, the evidence is inconclusive about the effectiveness of hormonal treatment in the management of patients with ED, even in patients with low testosterone levels. Trials comparing testosterone (in oral, injection, gel, patch, and cream forms) with placebo in hypogonadal men with ED were small, were of low quality, or reported inconsistent effects on erectile function. Clinicians should individualize decisions to measure hormone levels on the basis of the clinical presentation (for example, decreased libido, premature ejaculation, and fatigue) and physical findings (for example, testicular atrophy and muscle atrophy) that suggest hormonal abnormality.

See the Figure for a summary of the recommendations and clinical considerations. The Table describes the American College of Physicians' guideline grading system.

Grahic Jump Location
Figure.
The American College of Physicians guideline on hormonal testing and pharmacologic treatment of erectile dysfunction.

PDE-5 = phosphodiesterase-5.

Grahic Jump Location
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Tan HM, Chin CM, Chua CB, Gatchalian E, Kongkanand A, Moh CL. et al.  Efficacy and tolerability of vardenafil in Asian men with erectile dysfunction. Asian J Androl. 2008; 10:495-502. PubMed
 
Miner M, Gilderman L, Bailen J, Cook D, Dawson K, Stanislaus M. et al.  Vardenafil in men with stable statin therapy and dyslipidemia. J Sex Med. 2008; 5:1455-67. PubMed
 
Mirone V, Costa P, Damber JE, Holmes S, Moncada I, Van Ahlen H, et al.  An evaluation of an alternative dosing regimen with tadalafil, 3 times/week, for men with erectile dysfunction: SURE study in 14 European countries. Eur Urol. 2005;47:846-54; discussion 854. [PMID: 15925082]
 
Young JM, Feldman RA, Auerbach SM, Kaufman JM, Garcia CS, Shen W. et al.  Tadalafil improved erectile function at twenty-four and thirty-six hours after dosing in men with erectile dysfunction: US trial. J Androl. 2005; 26:310-8. PubMed
 
McMahon CG, Stuckey BG, Lording DW, Wittert GA, Murphy A, Shin J. et al.  A 6-month study of the efficacy and safety of tadalafil in the treatment of erectile dysfunction: a randomised, double-blind, parallel-group, placebo-controlled study in Australian men. Int J Clin Pract. 2005; 59:143-9. PubMed
 
Carson C, Shabsigh R, Segal S, Murphy A, Fredlund P, Kuepfer C, Trial Evaluating the Activity of Tadalafil for Erectile Dysfunction-United States (TREATED-US) Study Group.  Efficacy, safety, and treatment satisfaction of tadalafil versus placebo in patients with erectile dysfunction evaluated at tertiary-care academic centers. Urology. 2005; 65:353-9. PubMed
 
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Staab A, Tillmann C, Forgue ST, Mackie A, Allerheiligen SR, Rapado J. et al.  Population dose-response model for tadalafil in the treatment of male erectile dysfunction. Pharm Res. 2004; 21:1463-70. PubMed
 
Montorsi F, Nathan HP, McCullough A, Brock GB, Broderick G, Ahuja S. et al.  Tadalafil in the treatment of erectile dysfunction following bilateral nerve sparing radical retropubic prostatectomy: a randomized, double-blind, placebo controlled trial. J Urol. 2004; 172:1036-41. PubMed
 
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Aversa A, Greco E, Bruzziches R, Pili M, Rosano G, Spera G.  Relationship between chronic tadalafil administration and improvement of endothelial function in men with erectile dysfunction: a pilot study. Int J Impot Res. 2007; 19:200-7. PubMed
 
McVary KT, Roehrborn CG, Kaminetsky JC, Auerbach SM, Wachs B, Young JM. et al.  Tadalafil relieves lower urinary tract symptoms secondary to benign prostatic hyperplasia. J Urol. 2007; 177:1401-7. PubMed
 
Saylan M, Khalaf I, Kadioglu A, Shoair KZ, Beheiry A, Wang WC. et al.  Efficacy of tadalafil in Egyptian and Turkish men with erectile dysfunction. Int J Clin Pract. 2006; 60:812-9. PubMed
 
Rajfer J, Aliotta PJ, Steidle CP, Fitch WP 3rd, Zhao Y, Yu A.  Tadalafil dosed once a day in men with erectile dysfunction: a randomized, double-blind, placebo-controlled study in the US. Int J Impot Res. 2007; 19:95-103. PubMed
 
Yip WC, Chiang HS, Mendoza JB, Tan HM, Li MK, Wang WC. et al.  Efficacy and safety of on demand tadalafil in the treatment of East and Southeast Asian men with erectile dysfunction: a randomized double-blind, parallel, placebo-controlled clinical study. Asian J Androl. 2006; 8:685-92. PubMed
 
Guo YL, Zhu JC, Pan TM, Ding Q, Wang YX, Cheong NF. et al.  Efficacy and safety of on-demand tadalafil for the treatment of erectile dysfunction in South-East Asian men. Int J Urol. 2006; 13:721-7. PubMed
 
Nagao K, Kimoto Y, Marumo K, Tsujimura A, Vail GM, Watts S. et al.  Efficacy and safety of tadalafil 5, 10, and 20 mg in Japanese men with erectile dysfunction: results of a multicenter, randomized, double-blind, placebo-controlled study. Urology. 2006; 68:845-51. PubMed
 
Incrocci L, Slagter C, Slob AK, Hop WC.  A randomized, double-blind, placebo-controlled, cross-over study to assess the efficacy of tadalafil (Cialis) in the treatment of erectile dysfunction following three-dimensional conformal external-beam radiotherapy for prostatic carcinoma. Int J Radiat Oncol Biol Phys. 2006; 66:439-44. PubMed
 
Choi HK, Kim JJ, Kim SC, Suh J, Park YK, Choi S. et al.  A randomised, double-blind, parallel, placebo-controlled study of the efficacy and safety of Tadalafil administered on-demand to men with erectile dysfunction in Korea. Taehan Pinyogikwa Hakhoe Chapchi. 2006; 47:852-58.
 
Bocchio M, Pelliccione F, Passaquale G, Mihalca R, Necozione S, Desideri G. et al.  Inhibition of phosphodiesterase type 5 with tadalafil is associated to an improved activity of circulating angiogenic cells in men with cardiovascular risk factors and erectile dysfunction. Atherosclerosis. 2008; 196:313-9. PubMed
 
Hatzichristou D, Gambla M, Rubio-Aurioles E, Buvat J, Brock GB, Spera G. et al.  Efficacy of tadalafil once daily in men with diabetes mellitus and erectile dysfunction. Diabet Med. 2008; 25:138-46. PubMed
 
Paick JS, Kim SW, Yang DY, Kim JJ, Lee SW, Ahn TY. et al.  The efficacy and safety of udenafil, a new selective phosphodiesterase type 5 inhibitor, in patients with erectile dysfunction. J Sex Med. 2008; 5:946-53. PubMed
 
Eardley I, Mirone V, Montorsi F, Ralph D, Kell P, Warner MR. et al.  An open-label, multicentre, randomized, crossover study comparing sildenafil citrate and tadalafil for treating erectile dysfunction in men naïve to phosphodiesterase 5 inhibitor therapy. BJU Int. 2005; 96:1323-32. PubMed
 
von Keitz A, Rajfer J, Segal S, Murphy A, Denne J, Costigan T, et al.  A multicenter, randomized, double-blind, crossover study to evaluate patient preference between tadalafil and sildenafil. Eur Urol. 2004;45:499-507; discussion 507-9. [PMID: 15041116]
 
Govier F, Potempa AJ, Kaufman J, Denne J, Kovalenko P, Ahuja S.  A multicenter, randomized, double-blind, crossover study of patient preference for tadalafil 20 mg or sildenafil citrate 50 mg during initiation of treatment for erectile dysfunction. Clin Ther. 2003; 25:2709-23. PubMed
 
Tolrà JR, Campaña JM, Ciutat LF, Miranda EF.  Prospective, randomized, open-label, fixed-dose, crossover study to establish preference of patients with erectile dysfunction after taking the three PDE-5 inhibitors. J Sex Med. 2006; 3:901-9. PubMed
 
Paick JS, Ahn TY, Choi HK, Chung WS, Kim JJ, Kim SC. et al.  Efficacy and safety of mirodenafil, a new oral phosphodiesterase type 5 inhibitor, for treatment of erectile dysfunction. J Sex Med. 2008; 5:2672-80. PubMed
 
Paick JS, Choi HK, Kim SC, Ahn TY, Kim JJ, Park JK. et al.  Efficacy and safety of oral SK3530 for the treatment of erectile dysfunction in Korean men: a multicenter, randomized, double-blind, placebo-controlled, fixed dose, parallel group clinical trial. Asian J Androl. 2008; 10:791-8. PubMed
 
Cavallini G, Modenini F, Vitali G, Koverech A.  Acetyl-L-carnitine plus propionyl-L-carnitine improve efficacy of sildenafil in treatment of erectile dysfunction after bilateral nerve-sparing radical retropubic prostatectomy. Urology. 2005; 66:1080-5. PubMed
 
Perimenis P, Markou S, Gyftopoulos K, Giannitsas K, Athanasopoulos A, Liatsikos E. et al.  Efficacy of apomorphine and sildenafil in men with nonarteriogenic erectile dysfunction. A comparative crossover study. Andrologia. 2004; 36:106-10. PubMed
 
Eardley I, Wright P, MacDonagh R, Hole J, Edwards A.  An open-label, randomized, flexible-dose, crossover study to assess the comparative efficacy and safety of sildenafil citrate and apomorphine hydrochloride in men with erectile dysfunction. BJU Int. 2004; 93:1271-5. PubMed
 
Perimenis P, Gyftopoulos K, Giannitsas K, Markou SA, Tsota I, Chrysanthopoulou A. et al.  A comparative, crossover study of the efficacy and safety of sildenafil and apomorphine in men with evidence of arteriogenic erectile dysfunction. Int J Impot Res. 2004; 16:2-7. PubMed
 
Pavone C, Curto F, Anello G, Serretta V, Almasio PL, Pavone-Macaluso M.  Prospective, randomized, crossover comparison of sublingual apomorphine (3 mg) with oral sildenafil (50 mg) for male erectile dysfunction. J Urol. 2004; 172:2347-9. PubMed
 
Porst H, Behre HM, Jungwirth A, Burkart M.  Comparative trial of treatment satisfaction, efficacy and tolerability of sildenafil versus apomorphine in erectile dysfunction—an open, randomized cross-over study with flexible dosing. Eur J Med Res. 2007; 12:61-7. PubMed
 
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Perimenis P, Karkoulias K, Konstantinopoulos A, Perimeni PP, Katsenis G, Athanasopoulos A. et al.  Sildenafil versus continuous positive airway pressure for erectile dysfunction in men with obstructive sleep apnea: a comparative study of their efficacy and safety and the patient's satisfaction with treatment. Asian J Androl. 2007; 9:259-64. PubMed
 
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Choppin A, Blue DR, Hegde SS, Gennevois D, McKinnon SA, Mokatrin A. et al.  Evaluation of oral ro70-0004/003, an alpha1A-adrenoceptor antagonist, in the treatment of male erectile dysfunction. Int J Impot Res. 2001; 13:157-61. PubMed
 
Kaplan SA, Gonzalez RR, Te AE.  Combination of alfuzosin and sildenafil is superior to monotherapy in treating lower urinary tract symptoms and erectile dysfunction. Eur Urol. 2007; 51:1717-23. PubMed
 
Diamond LE, Earle DC, Garcia WD, Spana C.  Co-administration of low doses of intranasal PT-141, a melanocortin receptor agonist, and sildenafil to men with erectile dysfunction results in an enhanced erectile response. Urology. 2005; 65:755-9. PubMed
 
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Bank AJ, Kelly AS, Kaiser DR, Crawford WW, Waxman B, Schow DA. et al.  The effects of quinapril and atorvastatin on the responsiveness to sildenafil in men with erectile dysfunction. Vasc Med. 2006; 11:251-7. PubMed
 
Safarinejad MR.  Salvage of sildenafil failures with cabergoline: a randomized, double-blind, placebo-controlled study. Int J Impot Res. 2006; 18:550-8. PubMed
 
Herrmann HC, Levine LA, Macaluso J Jr, Walsh M, Bradbury D, Schwartz S. et al.  Can atorvastatin improve the response to sildenafil in men with erectile dysfunction not initially responsive to sildenafil? Hypothesis and pilot trial results. J Sex Med. 2006; 3:303-8. PubMed
 
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Seftel AD, Mack RJ, Secrest AR, Smith TM.  Restorative increases in serum testosterone levels are significantly correlated to improvements in sexual functioning. J Androl. 2004; 25:963-72. PubMed
 
Shabsigh R, Kaufman JM, Steidle C, Padma-Nathan H.  Randomized study of testosterone gel as adjunctive therapy to sildenafil in hypogonadal men with erectile dysfunction who do not respond to sildenafil alone. J Urol. 2004; 172:658-63. PubMed
 
Cavallini G, Caracciolo S, Vitali G, Modenini F, Biagiotti G.  Carnitine versus androgen administration in the treatment of sexual dysfunction, depressed mood, and fatigue associated with male aging. Urology. 2004; 63:641-6. PubMed
 
Aversa A, Isidori AM, Spera G, Lenzi A, Fabbri A.  Androgens improve cavernous vasodilation and response to sildenafil in patients with erectile dysfunction. Clin Endocrinol (Oxf). 2003; 58:632-8. PubMed
 
Clopper RR, Voorhess ML, MacGillivray MH, Lee PA, Mills B.  Psychosexual behavior in hypopituitary men: a controlled comparison of gonadotropin and testosterone replacement. Psychoneuroendocrinology. 1993; 18:149-61. PubMed
 
Boyanov MA, Boneva Z, Christov VG.  Testosterone supplementation in men with type 2 diabetes, visceral obesity and partial androgen deficiency. Aging Male. 2003; 6:1-7. PubMed
 
Rabkin JG, Wagner GJ, Rabkin R.  A double-blind, placebo-controlled trial of testosterone therapy for HIV-positive men with hypogonadal symptoms. Arch Gen Psychiatry. 2000;57:141-7; discussion 155-6. [PMID: 10665616]
 
Shamloul R, Ghanem H, Fahmy I, El-Meleigy A, Ashoor S, Elnashaar A. et al.  Testosterone therapy can enhance erectile function response to sildenafil in patients with PADAM: a pilot study. J Sex Med. 2005; 2:559-64. PubMed
 
Schiavi RC, White D, Mandeli J, Levine AC.  Effect of testosterone administration on sexual behavior and mood in men with erectile dysfunction. Arch Sex Behav. 1997; 26:231-41. PubMed
 
Yassin AA, Saad F, Diede HE.  Testosterone and erectile function in hypogonadal men unresponsive to tadalafil: results from an open-label uncontrolled study. Andrologia. 2006; 38:61-8. PubMed
 
Seidman SN, Roose SP.  The sexual effects of testosterone replacement in depressed men: randomized, placebo-controlled clinical trial. J Sex Marital Ther. 2006; 32:267-73. PubMed
 
Gomaa AA, Hamed HA.  Improvement of sexual function in partial testosterone-deficient ageing men treated with cream containing testosterone and vasoactive agents. J Mens Health Gend. 2006; 3:47-55.
 
Merza Z, Blumsohn A, Mah PM, Meads DM, McKenna SP, Wylie K. et al.  Double-blind placebo-controlled study of testosterone patch therapy on bone turnover in men with borderline hypogonadism. Int J Androl. 2006; 29:381-91. PubMed
 
Chiang HS, Hwang TI, Hsui YS, Lin YC, Chen HE, Chen GC. et al.  Transdermal testosterone gel increases serum testosterone levels in hypogonadal men in Taiwan with improvements in sexual function. Int J Impot Res. 2007; 19:411-7. PubMed
 
Margo CE, French DD.  Ischemic optic neuropathy in male veterans prescribed phosphodiesterase-5 inhibitors. Am J Ophthalmol. 2007; 143:538-9. PubMed
 
McEvoy GK.  AHFS Drug Information. Bethesda, MD: American Soc of Health-System Pharmacists; 2008.
 

Figures

Grahic Jump Location
Figure.
The American College of Physicians guideline on hormonal testing and pharmacologic treatment of erectile dysfunction.

PDE-5 = phosphodiesterase-5.

Grahic Jump Location

Tables

Table Jump PlaceholderTable.  The American College of Physicians' Guideline Grading System

Videos

Video News Release - Guideline on the Benefits and Risks of PED-5 Inhibitor Drugs

References

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van Ahlen H, Wahle K, Kupper W, Yassin A, Reblin T, Neureither M.  Safety and efficacy of vardenafil, a selective phosphodiesterase 5 inhibitor, in patients with erectile dysfunction and arterial hypertension treated with multiple antihypertensives. J Sex Med. 2005; 2:856-64. PubMed
 
Goldstein I, Fisher WA, Sand M, Rosen RC, Mollen M, Brock G, et al. Vardenafil Study Group.  Women's sexual function improves when partners are administered vardenafil for erectile dysfunction: a prospective, randomized, double-blind, placebo-controlled trial. J Sex Med. 2005; 2:819-32. PubMed
 
Rosen R, Shabsigh R, Berber M, Assalian P, Menza M, Rodriguez-Vela L, et al. Vardenafil Study Site Investigators.  Efficacy and tolerability of vardenafil in men with mild depression and erectile dysfunction: the depression-related improvement with vardenafil for erectile response study. Am J Psychiatry. 2006; 163:79-87. PubMed
 
Edwards D, Hackett G, Collins O, Curram J.  Vardenafil improves sexual function and treatment satisfaction in couples affected by erectile dysfunction (ED): a randomized, double-blind, placebo-controlled trial in PDE5 inhibitor-naïve men with ED and their partners. J Sex Med. 2006; 3:1028-36. PubMed
 
Porst H, Sharlip ID, Hatzichristou D, Rubio-Aurioles E, Gittelman M, Stancil BN, et al; Vardenafil Study Group.  Extended duration of efficacy of vardenafil when taken 8 hours before intercourse: a randomized, double-blind, placebo-controlled study. Eur Urol. 2006;50:1086-94; discussion 1094-5. [PMID: 16820261]
 
Mazo E, Gamidov S, Iremashvili V.  The effect of vardenafil on endothelial function of brachial and cavernous arteries. Int J Impot Res. 2006; 18:464-9. PubMed
 
Ziegler D, Merfort F, van Ahlen H, Yassin A, Reblin T, Neureither M.  Efficacy and safety of flexible-dose vardenafil in men with type 1 diabetes and erectile dysfunction. J Sex Med. 2006; 3:883-91. PubMed
 
Ishii N, Nagao K, Fujikawa K, Tachibana T, Iwamoto Y, Kamidono S.  Vardenafil 20-mg demonstrated superior efficacy to 10-mg in Japanese men with diabetes mellitus suffering from erectile dysfunction. Int J Urol. 2006; 13:1066-72. PubMed
 
Demir E, Balal M, Paydas S, Sertdemir Y, Erken U.  Efficacy and safety of vardenafil in renal transplant recipients with erectile dysfunction. Transplant Proc. 2006; 38:1379-81. PubMed
 
Zumbé J, Porst H, Sommer F, Grohmann W, Beneke M, Ulbrich E.  Comparable efficacy of once-daily versus on-demand vardenafil in men with mild-to-moderate erectile dysfunction: findings of the RESTORE study. Eur Urol. 2008; 54:204-10. PubMed
 
Ralph D, Eardley I, Kell P, Dean J, Hackett G, Collins O. et al.  Improvement in erectile function on vardenafil treatment correlates with treatment satisfaction in both patients and their partners. BJU Int. 2007; 100:130-6. PubMed
 
Montorsi F, Brock G, Lee J, Shapiro J, Van Poppel H, Graefen M. et al.  Effect of nightly versus on-demand vardenafil on recovery of erectile function in men following bilateral nerve-sparing radical prostatectomy. Eur Urol. 2008; 54:924-31. PubMed
 
Tan HM, Chin CM, Chua CB, Gatchalian E, Kongkanand A, Moh CL. et al.  Efficacy and tolerability of vardenafil in Asian men with erectile dysfunction. Asian J Androl. 2008; 10:495-502. PubMed
 
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Carson C, Shabsigh R, Segal S, Murphy A, Fredlund P, Kuepfer C, Trial Evaluating the Activity of Tadalafil for Erectile Dysfunction-United States (TREATED-US) Study Group.  Efficacy, safety, and treatment satisfaction of tadalafil versus placebo in patients with erectile dysfunction evaluated at tertiary-care academic centers. Urology. 2005; 65:353-9. PubMed
 
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Seftel AD, Wilson SK, Knapp PM, Shin J, Wang WC, Ahuja S.  The efficacy and safety of tadalafil in United States and Puerto Rican men with erectile dysfunction. J Urol. 2004; 172:652-7. PubMed
 
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Rosen RC, Padma-Nathan H, Shabsigh R, Saikali K, Watkins V, Pullman W.  Determining the earliest time within 30 minutes to erectogenic effect after tadalafil 10 and 20 mg: a multicenter, randomized, double-blind, placebo-controlled, at-home study. J Sex Med. 2004; 1:193-200. PubMed
 
Aversa A, Greco E, Bruzziches R, Pili M, Rosano G, Spera G.  Relationship between chronic tadalafil administration and improvement of endothelial function in men with erectile dysfunction: a pilot study. Int J Impot Res. 2007; 19:200-7. PubMed
 
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Rajfer J, Aliotta PJ, Steidle CP, Fitch WP 3rd, Zhao Y, Yu A.  Tadalafil dosed once a day in men with erectile dysfunction: a randomized, double-blind, placebo-controlled study in the US. Int J Impot Res. 2007; 19:95-103. PubMed
 
Yip WC, Chiang HS, Mendoza JB, Tan HM, Li MK, Wang WC. et al.  Efficacy and safety of on demand tadalafil in the treatment of East and Southeast Asian men with erectile dysfunction: a randomized double-blind, parallel, placebo-controlled clinical study. Asian J Androl. 2006; 8:685-92. PubMed
 
Guo YL, Zhu JC, Pan TM, Ding Q, Wang YX, Cheong NF. et al.  Efficacy and safety of on-demand tadalafil for the treatment of erectile dysfunction in South-East Asian men. Int J Urol. 2006; 13:721-7. PubMed
 
Nagao K, Kimoto Y, Marumo K, Tsujimura A, Vail GM, Watts S. et al.  Efficacy and safety of tadalafil 5, 10, and 20 mg in Japanese men with erectile dysfunction: results of a multicenter, randomized, double-blind, placebo-controlled study. Urology. 2006; 68:845-51. PubMed
 
Incrocci L, Slagter C, Slob AK, Hop WC.  A randomized, double-blind, placebo-controlled, cross-over study to assess the efficacy of tadalafil (Cialis) in the treatment of erectile dysfunction following three-dimensional conformal external-beam radiotherapy for prostatic carcinoma. Int J Radiat Oncol Biol Phys. 2006; 66:439-44. PubMed
 
Choi HK, Kim JJ, Kim SC, Suh J, Park YK, Choi S. et al.  A randomised, double-blind, parallel, placebo-controlled study of the efficacy and safety of Tadalafil administered on-demand to men with erectile dysfunction in Korea. Taehan Pinyogikwa Hakhoe Chapchi. 2006; 47:852-58.
 
Bocchio M, Pelliccione F, Passaquale G, Mihalca R, Necozione S, Desideri G. et al.  Inhibition of phosphodiesterase type 5 with tadalafil is associated to an improved activity of circulating angiogenic cells in men with cardiovascular risk factors and erectile dysfunction. Atherosclerosis. 2008; 196:313-9. PubMed
 
Hatzichristou D, Gambla M, Rubio-Aurioles E, Buvat J, Brock GB, Spera G. et al.  Efficacy of tadalafil once daily in men with diabetes mellitus and erectile dysfunction. Diabet Med. 2008; 25:138-46. PubMed
 
Paick JS, Kim SW, Yang DY, Kim JJ, Lee SW, Ahn TY. et al.  The efficacy and safety of udenafil, a new selective phosphodiesterase type 5 inhibitor, in patients with erectile dysfunction. J Sex Med. 2008; 5:946-53. PubMed
 
Eardley I, Mirone V, Montorsi F, Ralph D, Kell P, Warner MR. et al.  An open-label, multicentre, randomized, crossover study comparing sildenafil citrate and tadalafil for treating erectile dysfunction in men naïve to phosphodiesterase 5 inhibitor therapy. BJU Int. 2005; 96:1323-32. PubMed
 
von Keitz A, Rajfer J, Segal S, Murphy A, Denne J, Costigan T, et al.  A multicenter, randomized, double-blind, crossover study to evaluate patient preference between tadalafil and sildenafil. Eur Urol. 2004;45:499-507; discussion 507-9. [PMID: 15041116]
 
Govier F, Potempa AJ, Kaufman J, Denne J, Kovalenko P, Ahuja S.  A multicenter, randomized, double-blind, crossover study of patient preference for tadalafil 20 mg or sildenafil citrate 50 mg during initiation of treatment for erectile dysfunction. Clin Ther. 2003; 25:2709-23. PubMed
 
Tolrà JR, Campaña JM, Ciutat LF, Miranda EF.  Prospective, randomized, open-label, fixed-dose, crossover study to establish preference of patients with erectile dysfunction after taking the three PDE-5 inhibitors. J Sex Med. 2006; 3:901-9. PubMed
 
Paick JS, Ahn TY, Choi HK, Chung WS, Kim JJ, Kim SC. et al.  Efficacy and safety of mirodenafil, a new oral phosphodiesterase type 5 inhibitor, for treatment of erectile dysfunction. J Sex Med. 2008; 5:2672-80. PubMed
 
Paick JS, Choi HK, Kim SC, Ahn TY, Kim JJ, Park JK. et al.  Efficacy and safety of oral SK3530 for the treatment of erectile dysfunction in Korean men: a multicenter, randomized, double-blind, placebo-controlled, fixed dose, parallel group clinical trial. Asian J Androl. 2008; 10:791-8. PubMed
 
Cavallini G, Modenini F, Vitali G, Koverech A.  Acetyl-L-carnitine plus propionyl-L-carnitine improve efficacy of sildenafil in treatment of erectile dysfunction after bilateral nerve-sparing radical retropubic prostatectomy. Urology. 2005; 66:1080-5. PubMed
 
Perimenis P, Markou S, Gyftopoulos K, Giannitsas K, Athanasopoulos A, Liatsikos E. et al.  Efficacy of apomorphine and sildenafil in men with nonarteriogenic erectile dysfunction. A comparative crossover study. Andrologia. 2004; 36:106-10. PubMed
 
Eardley I, Wright P, MacDonagh R, Hole J, Edwards A.  An open-label, randomized, flexible-dose, crossover study to assess the comparative efficacy and safety of sildenafil citrate and apomorphine hydrochloride in men with erectile dysfunction. BJU Int. 2004; 93:1271-5. PubMed
 
Perimenis P, Gyftopoulos K, Giannitsas K, Markou SA, Tsota I, Chrysanthopoulou A. et al.  A comparative, crossover study of the efficacy and safety of sildenafil and apomorphine in men with evidence of arteriogenic erectile dysfunction. Int J Impot Res. 2004; 16:2-7. PubMed
 
Pavone C, Curto F, Anello G, Serretta V, Almasio PL, Pavone-Macaluso M.  Prospective, randomized, crossover comparison of sublingual apomorphine (3 mg) with oral sildenafil (50 mg) for male erectile dysfunction. J Urol. 2004; 172:2347-9. PubMed
 
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Perimenis P, Karkoulias K, Konstantinopoulos A, Perimeni PP, Katsenis G, Athanasopoulos A. et al.  Sildenafil versus continuous positive airway pressure for erectile dysfunction in men with obstructive sleep apnea: a comparative study of their efficacy and safety and the patient's satisfaction with treatment. Asian J Androl. 2007; 9:259-64. PubMed
 
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Choppin A, Blue DR, Hegde SS, Gennevois D, McKinnon SA, Mokatrin A. et al.  Evaluation of oral ro70-0004/003, an alpha1A-adrenoceptor antagonist, in the treatment of male erectile dysfunction. Int J Impot Res. 2001; 13:157-61. PubMed
 
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Summary for Patients

Hormonal Testing and Pharmacologic Treatment of Erectile Dysfunction

The summary below is from the full reports titled “Hormonal Testing and Pharmacologic Treatment of Erectile Dysfunction: A Clinical Practice Guideline From the American College of Physicians” and “Oral Phosphodiesterase-5 Inhibitors and Hormonal Treatments for Erectile Dysfunction: A Systematic Review and Meta-analysis.” They are in the 3 November 2009 issue of Annals of Internal Medicine (volume 151, pages 639-649 and pages 650-661). The authors of the first report are A. Qaseem, V. Snow, T.D. Denberg, D.E. Casey Jr., M.A. Forciea, D.K. Owens, and P. Shekelle, for the Clinical Efficacy Assessment Subcommittee of the American College of Physicians; the authors of the second report are A. Tsertsvadze, H.A. Fink, F. Yazdi, R. MacDonald, A.J. Bella, M.T. Ansari, C. Garritty, K. Soares-Weiser, R. Daniel, M. Sampson, S. Fox, D. Moher, and T.J. Wilt.

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