Indications and early results of sildenafil (Viagra) in erectile dysfunction

Urology. 1999 Dec;54(6):1073-7. doi: 10.1016/s0090-4295(99)00310-6.


Objectives: To assess the acceptability, feasibility, and early results of sildenafil (Viagra) in a nonselected cohort of 316 patients (median age 58 years) who sought treatment for male sexual dysfunction during a 10-week period.

Methods: Erectile status and activity were evaluated by questionnaire; erectile function was assessed by pharmacologic testing and visual sexual stimulation. Cardiovascular contraindications were assessed. Patients selected for the trial received treatment for 2 months. Results based on the possibility of penetration and individual satisfaction (scale from 0 to 10) were classified as good, fair, or bad. Multifactorial analysis was performed to define factors influencing the response to sildenafil.

Results: Twenty-five percent of the patients from the initial cohort refused or did not meet the criteria for oral treatment; 25% of the remaining had a cardiovascular contraindication. At the end of the trial, 157 patients (88.7%) had completed the study; the efficacy of and satisfaction with sildenafil were considered good for 50 (31.84%), fair for 46 (29.29%), and bad for 61 (38.85%). Spontaneous nocturnal erections, organic etiologies, especially cavernovenous impotence, and previous treatment with self-intracavernous injections were significant factors influencing responses to oral treatment. Finally, 32% of the patients after completing the trial (17.2% of the initial cohort) were using sildenafil as their sole treatment, 34% chose self-intracavernous injections, and 25% decided to alternate between oral and local therapy.

Conclusions: In the present study, sildenafil had a 60% efficacy rate and was chosen as the sole treatment by only 30% of the patients tested. We propose pretreatment tests to help to predict the response to this medication.

Publication types

  • Clinical Trial

MeSH terms

  • Adult
  • Aged
  • Aged, 80 and over
  • Cohort Studies
  • Erectile Dysfunction / drug therapy*
  • Feasibility Studies
  • Humans
  • Male
  • Middle Aged
  • Phosphodiesterase Inhibitors / therapeutic use*
  • Piperazines / therapeutic use*
  • Purines
  • Sildenafil Citrate
  • Sulfones


  • Phosphodiesterase Inhibitors
  • Piperazines
  • Purines
  • Sulfones
  • Sildenafil Citrate