title: Sildenafil affects olfactory function.
abstract: OBJECTIVE
  Sildenafil is the first member of a new class of oral drugs effective for erectile dysfunction. However, approximately 20% of patients complain about nasal congestion after sildenafil administration.
  
  
  METHODS
  Because nasal airflow and olfaction are closely linked, the sense of smell was evaluated in 20 young, healthy volunteers after the administration of 50 and 100 mg sildenafil, and placebo in a double-blinded, crossover study. Olfactory function was evaluated using a standardized and validated test (Sniffin' Sticks). To investigate a possible impact of G-protein beta3 subunit C825T polymorphism on the effect of sildenafil on olfaction the genotype of all subjects was determined.
  
  
  RESULTS
  The effect of sildenafil on olfaction was only present at a dose of 100 mg but not at a dose of 50 mg sildenafil. The genotypes TT, CC and TC of the G-protein beta3 C825T polymorphism had no impact on the change in olfactory function.
  
  
  CONCLUSIONS
  Higher sildenafil doses may produce decreased olfactory sensitivity.
authors.affiliation: Smell and Taste Clinic, Department of Otorhinolaryngology, University of Dresden Medical School, Dresden, Germany.
authors.forename: V
authors.initials: V
authors.lastname: Gudziol
authors.forename: M
authors.initials: M
authors.lastname: Mück-Weymann
authors.forename: O
authors.initials: O
authors.lastname: Seizinger
authors.forename: R
authors.initials: R
authors.lastname: Rauh
authors.forename: W
authors.initials: W
authors.lastname: Siffert
authors.forename: T
authors.initials: T
authors.lastname: Hummel
mesh_terms: D018592:Cross-Over Studies; D004311:Double-Blind Method; D005838:Genotype; D020962:Heterotrimeric GTP-Binding Proteins / Q000235:genetics; D006801:Humans; D008297:Male; D010726:Phosphodiesterase Inhibitors / Q000008:administration & dosage / Q000494:pharmacology*; D010879:Piperazines / Q000008:administration & dosage / Q000494:pharmacology*; D011110:Polymorphism, Genetic; D011687:Purines; D000068677:Sildenafil Citrate; D012903:Smell / Q000187:drug effects*; D013450:Sulfones
chemical_list: C454420:G-protein beta3 subunit; D010726:Phosphodiesterase Inhibitors; D010879:Piperazines; D011687:Purines; D013450:Sulfones; D000068677:Sildenafil Citrate; D020962:Heterotrimeric GTP-Binding Proteins