Evaluation of side effects of sildenafil in group of young healthy volunteers

Abstract

We evaluated the safety and side effects of sildenafil in a group of sexually active volunteers younger than 40 years under conditions without sexual stimulation. Single oral dose of 50 mg dildenafil (n = 20) or placebo (n= 20) was randomly administered to 40 sexually active volunteers with the mean age of 26.80 ± 5.29 in sildenafil group and 25.70 ± 4.95 in placebo group. All the subjects were informed about the study, but not about the medicine. The following tests were performed immediately before and 90 minutes after the administration of the medicine: resting heart rate, blood pressure, electrocardiogram, visual acuity, color vision. The subjects were also asked to describe any discomfort or difference. Mann Whitney U test was used for statistical analyses. The only statistically significant difference was between heart rates before and after the administration of the sildenafil (p = 0.02). Color vision, visual acuity tests yielded no differences. The decrease in blood pressure was not significant. The most common side effects were flushing (75% and 0%), headache (50% and 5%), dyspepsia (15% and 5%), unintentional incomplete sexual arousal (15% and 0%) and palpitation (15% and 10%) in groups of sildenafil and placebo, respectively. The only serious side effect requiring medical treatment was arthralgia on the knee in one subject. Although these side effects can be acceptable, the likelihood of these side effects needs to be made clear to potential users of this medication.

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References

  1. 1.

    Boolel M, Gepi-Attee S, Gingell JC, Allen MJ. Sidenafil. A novel effective oral therapy for male erectile dysfunction. Br J Urol 1996; 78: 257–261.

    Google Scholar 

  2. 2.

    Ballard SA et al. Sildenafil, an inhibitor of the phosphodiesterase type 5, enhances nitric oxide mediated relaxation of human corpus cavernosum. Int J Impot Res 1996; 8: 103 Abstract.

    Google Scholar 

  3. 3.

    Tarrett NK, Bell AS, Brown D, Ellis P. Sildenafil (Viagra), a potent and selective inhibitor of type 5 cGMP phosphodiesterase with utility for the treatment of male erectile dysfunction. Bioorganic and Medicinal Chemistry Letters 1996; 6: 1819–1824.

    Article  Google Scholar 

  4. 4.

    Goldstein I, Lue TF, Padma-Nathan H, Rosen RC, Steers WD, Wicker PA. For the Sildenafil Study Group. Oral Sildenafil in the Treatment of Erectile Dysfunction. N Engl J Med 1998; 338: 1397–1404.

    CAS  Google Scholar 

  5. 5.

    Wagner G, Saenz de Tejada I. Update on male erectile dysfunction. BMJ 1998; 316: 678–682.

    PubMed  CAS  Google Scholar 

  6. 6.

    Morales A, Gingell C, Collins M, Wicker PA, Osterloh IH. Clinical safety of oral sildenafil citrate (VIAGRATM) in the treatment of erectile dysfunction. Int J Impot Res 1998; 10: 69–74.

    PubMed  CAS  Article  Google Scholar 

  7. 7.

    Viagra deaths often occur within 4-5 hour - FDA safety update. FDC Pink 1998; 60: 11.

  8. 8.

    Padma-Nathan H, Steers WD, Wicker PA. Efficacy and safety oral sildenafil in the treatment of erectile dysfunction: A double blind, placebo controlled study of 329 patients. Int J Clin Practice 1998; 52(6): 375–379.

    CAS  Google Scholar 

  9. 9.

    31 deaths associated with Viagra in UK. Scrip 1999; 2471: 23.

    Google Scholar 

  10. 10.

    Walker DK, Ackland MJ, James GC, Muirhead GJ, Rance DJ, Wastall P, Wright PA. Pharmacokinetics and metabolism of sildenafil in mouse, rate, rabbit, dog and man. Xenobiotica 1999; 29(3): 297–310.

    PubMed  CAS  Article  Google Scholar 

  11. 11.

    Marks LS, Duda C, Dorey FJ, Macairan ML, Santos PB. Treatment of erectile dysfunction with sildenafil. Urology 1999; 53: 19–24.

    PubMed  CAS  Article  Google Scholar 

  12. 12.

    Jackson G, Benjamin N, Jackson N, Allen MJ. Effects of Sildenafil citrate on Human Hemodynamics. Am J Cardiol 1999; 83: 13C–20C.

    PubMed  CAS  Article  Google Scholar 

  13. 13.

    Randell MS, Rajfer J, Wicker PA, Smith MD. Sildenafil for treatment of erectile dysfunction in men with diabetes. JAMA 1999; 281: 421–426.

    Article  Google Scholar 

  14. 14.

    Wallis RM, Corbin JD, Francis SH, Ellis P. Tissue distribution of phosphodiesterase families and the effects of sildenafil on tissue cyclic nucleotides, platelet function, and the contractile responses of trabeculae carneae and aortic rings in vitro. Am J Cardiol 1999; 83: 3C–12C.

    PubMed  CAS  Article  Google Scholar 

  15. 15.

    Shirasaki Y, Su C, Lee TJ, Kolm P, Cline WH Jr et al. Endothelial modulation of vascular relaxation to nitrovasodilators in aging and hypertension. J Pharmacol Exp Ther 1986; 239(3): 861–866.

    PubMed  CAS  Google Scholar 

  16. 16.

    Center for drug evaluation and research. Viagra tablets (Sildenafil Citrate): Review and evaluation of pharmacology and toxicology data for NDA-20-895. Washington DC: Division of cardio-renal drug products, Center for Drug evaluation and Research, Food and Drug Administration, 1998, pp. 19–21.

    Google Scholar 

  17. 17.

    Center for drug evaluation and research. Animal Pharmacology: mechanism of action;section 4.2. In: Viagra (Sildenafil): Joint Clinical Review for NDA-20-895. Washington DC: Center for Drug evaluation and Research, Food and Drug Administration, 1998.

    Google Scholar 

  18. 18.

    Webb DJ, Boolell M, Muirhaed G. Cardiovascular effects of phosphodiestererase type 5 inhibition with concomitant nitrate therapy(abstract). Circulation 1998; 98(supp 17): I–637.

    Google Scholar 

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Dündar, M., Koçak, İ., Dündar, S.O. et al. Evaluation of side effects of sildenafil in group of young healthy volunteers. Int Urol Nephrol 32, 705–708 (2001). https://doi.org/10.1023/A:1015056416501

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  • Normal potency
  • Side effect
  • Sildenafil
  • Young volunteer