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A Risk-Benefit Assessment of Sildenafil in the Treatment of Erectile Dysfunction

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Abstract

Sildenafil is an oral treatment for erectile dysfunction (ED). It acts as an inhibitor of 3′,5′-cyclic guanosine monophosphate-phosphodiesterase type 5. An effective treatment for ED is required to produce an erectile response sufficient for satisfactory sexual performance. This has been documented for sildenafil in men with ED of differing aetiologies and baseline severity in various types of clinical trials.

Sildenafil treatment is characterised by a good tolerability profile and low treatment discontinuation rate caused by treatment-related adverse effects. Most of the adverse effects associated with sildenafil are extensions of the pharmacological action of the drug. There is no significant difference in the adverse effect profile (headache, flushing, dyspepsia, nasal congestion and abnormal vision) of this agent as assessed by clinical data obtained either in the pre- and postlaunch periods. Because of its acceptable risk-benefit ratio, sildenafil can be prescribed to a very large group of patients with ED. The reports of serious cardiovascular events associated with the use of sildenafil (including anecdotal reports of deaths) have been very thoroughly analysed. A number of studies have not shown any difference in the risk of serious cardiovascular events in sildenafil- and placebo-treated patients. However, when making a risk-benefit evaluation, certain subgroups of patients need to be considered separately. In particular, sildenafil is contraindicated in patients receiving nitrate therapy. In some other subgroups of patients, the risks and benefits of treatment need to be assessed on an individual basis and it is hoped that additional data will clarify any possible risks associated with sildenafil administration such patients.

It is helpful to compare the risk-benefit profile of sildenafil with the characteristics of other oral drugs for ED. According to the preliminary data, apomorphine and phentolamine are possible future options for the treatment of ED; however, there needs to be further clinical evaluation of these agents. Initial data have shown that sildenafil can be successfully combined with intracavernosal injection in patients nonresponders to either therapy.

In conclusion, favourable characteristics make sildenafil suitable for the first-line therapy for a substantial proportion of patients with ED.

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References

  1. NIH Consensus Development Panel on impotence: impotence. JAMA 1993; 270: 83–90

    Google Scholar 

  2. Feldman HA, Goldstein I, Hatzichristou DG, et al. Impotence and its medical and psychosocial correlates: results of the Massachusetts Male Aging Study. J Urol 1994; 151: 54–61

    PubMed  CAS  Google Scholar 

  3. Araujo AB, Durante R, Feldman HA, et al. The relationship between depressive symptoms and male erectile dysfunction: cross-sectional results from Massachusetts Male Aging Study. Psychosom Med 1998; 60: 458–65

    PubMed  CAS  Google Scholar 

  4. Rajfer J, Aronson WJ, Bush PA, et al. Nitric oxide as a mediator of relaxation of the corpus cavernosum in response to nonadrenergic, noncholinergic neurotransmission. N Engl J Med 1992; 326: 90–4

    Article  PubMed  CAS  Google Scholar 

  5. Burnett AL. Nitric oxide in the penis: physiology and pathology. J Urol 1997; 157: 320–4

    Article  PubMed  CAS  Google Scholar 

  6. Langtry HD, Markham A. Sildenafil: a review of its use in erectile dysfunction. Drugs 1999; 57: 967–89

    Article  PubMed  CAS  Google Scholar 

  7. Stief CG, Uckert S, Becker AJ, et al. Effects of sildenafil on cAMP and cGMP levels in isolated human cavernous and cardiac tissue. Urology 2000; 55: 146–50

    Article  PubMed  CAS  Google Scholar 

  8. Goldstein I, Lue TF, Padma-Nathan H, et al. Oral sildenafil in the treatment of erectile dysfunction. N Engl J Med 1998; 338: 1397–404

    Article  PubMed  CAS  Google Scholar 

  9. Padma-Nathan H, Steers WD, Wicker PA. Efficacy and safety of oral sildenafil in the treatment of erectile dysfunction: a double-blind, placebo-controlled study of 329 patients. Int J Clin Pract 1998; 52: 375–9

    PubMed  CAS  Google Scholar 

  10. Rendell MS, Rajfer J, Wicker PA, et al. Sildenafil for treatment of erectile dysfunction in men with diabetes. JAMA 1999; 281: 421–6

    Article  PubMed  CAS  Google Scholar 

  11. Conti CR, Pepine CJ, Sweeney M. Efficacy and safety of sildenafil citrate in the treatment of erectile dysfunction in patients with ischemic heart disease. Am J Cardiol 1999; 83: 29C–34C

    Article  PubMed  CAS  Google Scholar 

  12. Olsson AM, Persson CA. Efficacy and safety of Viagra (sildenafil citrate) in men with cardiovascular disease and erectile dysfunction. Annual Meeting of the American College of Cardiology; 2000 Mar 14; Anaheim. Available from URL: http://www.medscape.com/medscape/cno/2001/ACC/Story.cfm?story_id=1142 [Accessed 2001 Jan 31]

  13. Derry FA, Dinsmore WW, Fraser M, et al. Efficacy and safety of oral sildenafil (Viagra) in men with erectile dysfunction caused by spinal cord injury. Neurology 1998; 51: 1629–33

    Article  PubMed  CAS  Google Scholar 

  14. Jarow JP, Burnett AL, Geringer AM. Clinical efficacy of sildenafil citrate based on etiology and response to prior treatment. J Urol 1999; 162: 722–5

    Article  PubMed  CAS  Google Scholar 

  15. Rosen RC, Riley A, Wagner G, et al. The International Index of Erectile Function (IIEF): a multidimensional scale for assessment of erectile dysfunction. Urology 1997; 49: 822–30

    Article  PubMed  CAS  Google Scholar 

  16. Lowentritt BH, Scardino PT, Miles BJ, et al. Sildenafil citrate after radical retropubic prostatectomy. J Urol 1999; 162: 1614–7

    Article  PubMed  CAS  Google Scholar 

  17. Zippe CD, Jhaveri FM, Klein EA, et al. Role of Viagra after radical prostatectomy. Urology 2000; 55: 241–5

    Article  PubMed  CAS  Google Scholar 

  18. Morales A, Gingell C, Collins M, et al. Clinical safety of oral sildenafil citrate (Viagra) in the treatment of erectile dysfunction. Int J Impot Res 1998; 10: 69–74

    Article  PubMed  CAS  Google Scholar 

  19. Montorsi F, McDermott TE, Morgan R, et al. Efficacy and safety of fixed-dose oral sildenafil in the treatment of erectile dysfunction of various etiologies. Urology 1999; 53: 1011–8

    Article  PubMed  CAS  Google Scholar 

  20. Virag R. Indications and early results of sildenafil (Viagra) in erectile dysfunction. Urology 1999; 54: 1073–7

    Article  PubMed  CAS  Google Scholar 

  21. Moreira SG, Brannigan RE, Spitz A, et al. Side-effect profile of sildenafil citrate (Viagra) in clinical practice. Urology 2000; 56: 474–6

    Article  PubMed  Google Scholar 

  22. Kaplan SA, Reis RB, Kohn IJ, et al. Safety and efficacy of sildenafil in postmenopausal women with sexual dysfunction. Urology 1999; 53: 481–6

    Article  PubMed  CAS  Google Scholar 

  23. Jackson G, Benjamin N, Jackson N, et al. Effects of sildenafil citrate on human hemodynamics. Am J Cardiol 1999; 83: 13C–20C

    Article  PubMed  CAS  Google Scholar 

  24. Bortolotti M, Mari C, Lopilato C, et al. Effects of sildenafil on esophageal motility of patients with idiopathic achalasia. Gastroenterology 2000; 118: 253–7

    Article  PubMed  CAS  Google Scholar 

  25. Vobig MA, Klotz T, Staak M, et al. Retinal side-effects of sildenafil. Lancet 1999; 353: 375

    Article  PubMed  CAS  Google Scholar 

  26. Zrenner E. No cause for alarm over retinal side-effects of sildenafil. Lancet 1999; 353: 340–1

    Article  PubMed  CAS  Google Scholar 

  27. Gonzalez CM, Bervig T, Podlasek C, et al. Sildenafil causes a dose- and time-dependent downregulation of phosphodiesterase type 6 expression in the rat retina. Int J Impot Res 1999; 11Suppl. 1: 9–14

    Article  Google Scholar 

  28. Goldenberg MM. Safety and efficacy of sildenafil citrate in the treatment of male erectile dysfunction. Clin Ther 1998; 20: 1033–48

    Article  PubMed  CAS  Google Scholar 

  29. Food and Drug Administration. Summary of reports of death in Viagra users received from marketing (late March) through mid-November 1998. Available from URL: http://www.fda.gov/cder/consumerinfo/viagra/safety3.htm [Accessed 2001 Jan 31]

  30. Cheitlin MD, Hutter Jr AM, Brindis RG, et al. Use of sildenafil (Viagra) in patients with cardiovascular disease. Circulation 1999; 99: 168–77

    Article  PubMed  CAS  Google Scholar 

  31. Cheitlin MD, Hutter Jr AM, Brindis RG, et al. ACC/AHA expert consensus document. Use of sildenafil (Viagra) in patients with cardiovascular disease. J Am Coll Cardiol 1999; 33: 273–82

    Article  PubMed  CAS  Google Scholar 

  32. Zusman RM, Morales A, Glasser DB, et al. Overall cardiovascular profile of sildenafil citrate. Am J Cardiol 1999; 83: 35C–44C

    Article  PubMed  CAS  Google Scholar 

  33. Kloner RA, Zusman RM. Cardiovascular effects of sildenafil citrate and recommendations for its use. Am J Cardiol 1999; 84: 11–7

    Article  Google Scholar 

  34. Kloner RA. Cardiovascular risk and sildenafil. Am J Cardiol 2000; 86Suppl.: 57F–61F

    Article  PubMed  CAS  Google Scholar 

  35. Speakman MT. Viagra and cardiovascular disease. J Cardiovasc Pharmacol Ther 1999; 4: 259–67

    Article  PubMed  CAS  Google Scholar 

  36. Shakir S, Freemantle S, Pearce G. IHD morbidity and mortality in a community-based cohort of sildenafil users in England: phase 1 results [abstract]. In: Velo G, Leone R, editors. Abstracts of the 8th Annual Meeting European Society of Pharmacovigilance; 2000 Sep 21-23; Verona. Amsterdam: Elsevier, 2000: 14

  37. Webb DJ, Freestone S, Allen MJ, et al. Sildenafil citrate and blood-pressure-lowering drugs: results of drug interaction studies with an organic nitrate and a calcium antagonist. Am J Cardiol 1999; 83: 21C–28C

    Article  PubMed  CAS  Google Scholar 

  38. Webb DJ, Muirhead GJ, Wulff M, et al. Sildenafil citrate potentiates the hypotensive effects of nitric oxide donor drugs in male patients with stable angina. J Am Coll Cardiol 2000; 36: 25–31

    Article  PubMed  CAS  Google Scholar 

  39. Geelen P, Drolet B, Rail J, et al. Sildenafil (Viagra) prolongs cardiac repolarization by blocking the rapid component of the delayed rectifier potassium current. Circulation 2000; 102: 275–7

    Article  PubMed  CAS  Google Scholar 

  40. Awan GM, Calderon E, Dawood G, et al. Acute, symptomatic atrial fibrillation after sildenafil citrate therapy in a patient with hypertrophic obstructive cardiomyopathy. Am J Med Sci 2000; 320: 69–71

    Article  PubMed  CAS  Google Scholar 

  41. Pfizer US. Prescribing information. Viagra (sildenafil citrate). Revised version January 2000. Available from URL: http://www.pfizer.com/hml/pi’s/viagrapi.html [Accessed 2001 Jan 31]

  42. Padma Nathan H. Anew era in the treatment of erectile dysfunction. Am J Cardiol 1999; 84: 18–23

    Article  Google Scholar 

  43. Hoffman BB, Lefkowitz RJ. Catecholamines, sympathomimetic drugs, and adrenergic receptor antagonists. In: Hardman JG, Limbird LE, editors-in-chief. Goodman & Gilman’s the pharmacological basis of therapeutics. New York (NY): McGraw-Hill, 1996: 199–248

    Google Scholar 

  44. Hoffman BB. Adrenoceptor-blocking drugs. In: Katzung BG, editor. Basic and clinical pharmacology. East Norwalk (CT): Appleton & Lange, 1995: 132–46

  45. Telöken C, Rhoden EL, Sogari P, et al. Therapeutic effects of high dose yohimbine hydrochloride on organic erectile dysfunction. J Urol 1998; 159: 122–4

    Article  PubMed  Google Scholar 

  46. Kunelius P, Hakkinen J, Likkarinen O. Is high-dose yohimbine hydrochloride effective in the treatment of mixed-type impotence?: a prospective, randomised, controlled double-blind crossover study. Urology 1997; 49: 441–4

    Article  PubMed  CAS  Google Scholar 

  47. Montorsi F, Barbieri L, Strambi LF, et al. Effect of yohimbine-trazodone on psychogenic impotence: a randomised double-blind, placebo controlled study. Urology 1994; 44: 732–6

    Article  PubMed  CAS  Google Scholar 

  48. Ernst E, Pittler MH. Yohimbine for erectile dysfunction: a systematic review and meta-analysis of randomised clinical trials. J Urol 1998; 159: 433–6

    Article  PubMed  CAS  Google Scholar 

  49. Hollister LE. Antidepressant agent. In: Katzung BG, editor. Basic and clinical pharmacology. East Norwalk (CT): Appleton & Lange, 1995: 448–59

    Google Scholar 

  50. Lance R, Albo M, Costabile RA, et al. Oral trazodone as empirical therapy for erectile dysfunction: a retrospective review. Urology 1995; 46: 117–20

    Article  PubMed  CAS  Google Scholar 

  51. Meinhardt W, Schmitz PIM, Kropman RF, et al. Trazodone, a double blind trial for treatment of erectile dysfunction. Int J Impot Res 1997; 9: 163–5

    Article  PubMed  CAS  Google Scholar 

  52. Heaton JPW, Morales A, Adams MA, et al. Recovery of erectile function by the oral administration of apomorphine. Urology 1995; 45: 200–6

    Article  PubMed  CAS  Google Scholar 

  53. Traish A, Gupta S, Gallant C, et al. Phentolamine mesylate relaxes penile corpus cavernosum tissue by adrenergic and nonadrenergic mechanisms. Int J Impot Res 1998; 10: 215–23

    Article  PubMed  CAS  Google Scholar 

  54. Gwinup G. Oral phentolamine in nonspecific erectile insufficiency. Ann Intern Med 1988; 109: 162–3

    PubMed  CAS  Google Scholar 

  55. Zorgniotti AW. Experience with buccal phentolamine mesylate for impotence. Int J Impot Res 1994; 6: 37–41

    PubMed  CAS  Google Scholar 

  56. Becker AJ, Steif CG, Machtens S, et al. Oral phentolamine as treatment for erectile dysfunction. J Urol 1998; 159: 1214–6

    Article  PubMed  CAS  Google Scholar 

  57. Meinhardt W, de la Fuente RB, Lycklama à Nijeholt AAB, et al. Prostaglandin E-1 with phentolamine for the treatment of erectile dysfunction. J Urol 1996; 8: 5–7

    CAS  Google Scholar 

  58. Godschalk M, Gheorghiu D, Chen J, et al. Long-term efficacy of a new formulation of prostaglandin E-1 as treatment for erectile failure. J Urol 1996; 155: 915–7

    Article  PubMed  CAS  Google Scholar 

  59. Buvat J, Costa P, Morlier D, et al. Double-blind multicenter study comparing alprostadil α-cyclodextrin with moxisylyte chlorhydrate in patients with chronic erectile dysfunction. J Urol 1998; 159: 116–9

    Article  PubMed  CAS  Google Scholar 

  60. Linet OI, Ogring FG, Group AS. Efficacy and safety of intracavernosal alprostadil in men with erectile dysfunction. N Engl J Med 1996; 334: 873–7

    Article  PubMed  CAS  Google Scholar 

  61. Porst H. The rationale for prostaglandine E-1 in erectile failure; a survey of worldwide experience. J Urol 1996; 155: 802–15

    Article  PubMed  CAS  Google Scholar 

  62. Padma-Nathan H, Hellstrom WJG, Kaiser FE. Treatment of men with erectile dysfunction with transurethral alprostadil. N Engl J Med 1997; 336: 1–7

    Article  PubMed  CAS  Google Scholar 

  63. Porst H. Transurethral alprostadil with MUSE (medicated urethral system for erection) vs intracavernous alprostadil - a comparative study in 103 patients with erectile dysfunction. Int J Impotence Res 1997; 9: 187–92

    Article  CAS  Google Scholar 

  64. Utiger RD. A pill for impotence. N Engl J Med 1998; 338: 1458–9

    Article  PubMed  CAS  Google Scholar 

  65. McMahon CG, Samali R, Johnson H. Treatment of intracorporeal injection nonresponse with sildenafil alone or in combination with triple agent intracorporeal injection therapy. J Urol 1999; 162: 1992–7; discussion 1997-8

    Article  PubMed  CAS  Google Scholar 

  66. Krane RJ, Goldstein I, Saenz de Tajada I. Impotence. N Engl J Med 1989; 321: 1648–59

    Article  PubMed  CAS  Google Scholar 

  67. Warrington JS, Shader RI, Von Moltke LL, et al. In vitro biotransformation of sildenafil (Viagra): identification of human cytochromes and potential drug interactions. Drug Metab Disp 2000; 28: 392–7

    CAS  Google Scholar 

  68. Muirhead GJ, Wulff MB, Fielding A, et al. Pharmacokinetic interactions between sildenafil and saquinavir/ritonavir. Br J Clin Pharmacol 2000; 50: 99–107

    Article  PubMed  CAS  Google Scholar 

  69. Cohen JS. Should patients be given an initial low test dose of sildenafil? Drug Saf 2001; 23: 1–9

    Article  Google Scholar 

  70. Marmor MF, Kessler R. Sildenafil (Viagra) and ophthalmology. Surv Ophthalmol 1999; 44: 153–62

    Article  PubMed  CAS  Google Scholar 

  71. Kassim AA, Fabry ME, Nagel RL. Acute priapism associated with the use of sildenafil in a patient with sickle cell trait. Blood 2000; 95: 1878–9

    PubMed  CAS  Google Scholar 

  72. Sur RL, Kane CJ. Sildenafil citrate-associated priapism. Urology 2000; 55: 950

    Article  PubMed  CAS  Google Scholar 

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Vitezic, D. A Risk-Benefit Assessment of Sildenafil in the Treatment of Erectile Dysfunction. Drug-Safety 24, 255–265 (2001). https://doi.org/10.2165/00002018-200124040-00003

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