Alterations in sperm motility after acute oral administration of sildenafil or tadalafil in young, infertile men.
OBJECTIVE
To evaluate the acute effect of sildenafil and tadalafil on seminal parameters in young, infertile patients.


METHODS
Prospective, randomized, double-blind, crossover clinical investigation on semen parameters after the administration of a single dose of sildenafil (50 mg) or tadalafil (20 mg).


METHODS
An academic hospital as well as a male infertility center and clinical andrology laboratories.


METHODS
Eighteen young, infertile men.


METHODS
Oral administration of a single dose of sildenafil (50 mg) or tadalafil (20 mg) in a blind, randomized order. The semen samples were collected 1 or 2 hours after each treatment.


METHODS
Changes in sperm parameters after sildenafil and tadalafil administration, compared with the basal conditions.


RESULTS
A significant increase in sperm progressive motility (median value, 37.0% vs. 28.5%) was observed after sildenafil administration as compared with baseline; in contrast, a significant decreased value was observed after tadalafil (median value, 21.5% vs. 28.5%).


CONCLUSIONS
These preliminary results indicate that sperm motility appears to be acutely affected in young, infertile patients by a single dose of sildenafil and tadalafil, with opposite effects: stimulatory by the former and inhibitory by the latter.
Pomara
Giorgio
G
Urology Unit, Azienda Ospedaliera Pisana, University of Pisa, Pisa, Italy. g.pomara@libero.it
Morelli
Girolamo
G
Canale
Domenico
D
Turchi
Paolo
P
Caglieresi
Carolina
C
Moschini
Cecilia
C
Liguori
Giovanni
G
Selli
Cesare
C
Macchia
Enrico
E
Martino
Enio
E
Francesca
Francesco
F
D015106:3',5'-Cyclic-GMP Phosphodiesterases / Q000037:antagonists & inhibitors; D000328:Adult; D002243:Carbolines / Q000494:pharmacology*; D018592:Cross-Over Studies; D054706:Cyclic Nucleotide Phosphodiesterases, Type 5; D003864:Depression, Chemical; D004311:Double-Blind Method; D006801:Humans; D007248:Infertility, Male / Q000188:drug therapy*; D008297:Male; D010726:Phosphodiesterase Inhibitors / Q000494:pharmacology; D010727:Phosphoric Diester Hydrolases / Q000378:metabolism; D010879:Piperazines / Q000494:pharmacology*; D011687:Purines / Q000494:pharmacology; D000068677:Sildenafil Citrate; D013081:Sperm Motility / Q000187:drug effects*; D013268:Stimulation, Chemical; D013450:Sulfones / Q000494:pharmacology*; D000068581:Tadalafil
D002243:Carbolines; D010726:Phosphodiesterase Inhibitors; D010879:Piperazines; D011687:Purines; D013450:Sulfones; D000068581:Tadalafil; D000068677:Sildenafil Citrate; D010727:Phosphoric Diester Hydrolases; D015106:3',5'-Cyclic-GMP Phosphodiesterases; D054706:Cyclic Nucleotide Phosphodiesterases, Type 5; C406737:PDE11A protein, human; C517381:PDE5A protein, human