title: Characteristics of sildenafil erections in healthy young men.
abstract: OBJECTIVE
  To determine the effect of sildenafil citrate on the nocturnal penile erections (i.e. time to onset, the duration of erection, and the interval between first and second erections) of healthy young men.
  
  
  METHODS
  Twenty-two potent men, 23-29 years old, were recruited for the study. All subjects completed three sessions over consecutive nights using the RigiScan monitoring device (Dacomed, Minneapolis, USA). After a first night of adaptation, night 2 records were their baseline values, and on night 3 they received 100 mg of sildenafil citrate. Statistical comparisons were done between the second and third night data.
  
  
  RESULTS
  The mean time to onset of the first erection with sildenafil citrate was (34+/-18) min, whereas it was (74+/-24) min (P 0.0001) without sildenafil citrate. The number of erections observed during the first 5 h after sildenafil citrate medication was 3.6+/-0.5 in contrast to 2.4+/-0.5 with no medication (P=0.001). The interval between first and second erections was shorter with sildenafil citrate: (52+/-26) min vs. (85+/-34) min (P = 0.01). The duration of the last erection was statistically significantly longer with the sildenafil citrate: (64 +/-33) min vs. (42 +/-28) min (P 0.001).
  
  
  CONCLUSIONS
  Healthy young men achieved erection within 34 min after sildenafil citrate administration, which is shorter than the 1 h interval proposed by the manufacturer. The interval between the first and second erections was shorter and the duration of the last nocturnal erection was longer.
authors.affiliation: Department of Urology, University of Ankara, School of Medicine, Ankara, Turkey. yaman@medicine.ankara.edu.tr
authors.forename: Onder
authors.initials: O
authors.lastname: Yaman
authors.forename: Zafer
authors.initials: Z
authors.lastname: Tokatli
authors.forename: Murat
authors.initials: M
authors.lastname: Akand
authors.forename: Atilla H
authors.initials: AH
authors.lastname: Elhan
authors.forename: Kadri
authors.initials: K
authors.lastname: Anafarta
mesh_terms: D000284:Administration, Oral; D000328:Adult; D006801:Humans; D008297:Male; D010410:Penile Erection / Q000187:drug effects*; D010879:Piperazines / Q000008:administration & dosage*; D011687:Purines; D000068677:Sildenafil Citrate; D013450:Sulfones; D013997:Time Factors; D014665:Vasodilator Agents / Q000008:administration & dosage*
chemical_list: D010879:Piperazines; D011687:Purines; D013450:Sulfones; D014665:Vasodilator Agents; D000068677:Sildenafil Citrate