Phosphodiesterase 5 inhibitors for erectile dysfunction.
OBJECTIVE
To review the pharmacologic and clinical trial data of the Food and Drug Administration-approved phosphodiesterase 5 (PDE5) inhibitors for the treatment of erectile dysfunction (ED).


METHODS
Primary research and review articles were identified through a search of ScienceDirect, PubMed/MEDLINE, and International Pharmaceutical Abstracts (1990-August 2004). The following search terms were used in the Medicine Dentistry and Pharmacology, Toxicology, and Pharmaceutical Sciences subcategories: phosphodiesterase 5 inhibitor, PDE5 inhibitor, erectile dysfunction, sildenafil, vardenafil, tadalafil, prostatectomy, and diabetes. Web of Science (1990-August 2004) was used to search for additional abstracts using the same search terms as above. The package inserts for sildenafil, vardenafil, and tadalafil were also consulted.


METHODS
All identified research, review articles, and abstracts were assessed for relevance, and all relevant information was included. Priority was given to the primary medical literature and clinical trial reports.


RESULTS
ED is a common disorder in males with increased prevalence associated with age and presence of cardiovascular disease, prostatectomy, or diabetes mellitus. Sildenafil, vardenafil, and tadalafil are selective PDE5 inhibitors currently available for treatment of ED. Their pharmacology and pharmacokinetics vary slightly, but with potentially important clinical differences in duration of activity; all have similar clinical efficacy and adverse effect profiles in patients with ED of various causes.


CONCLUSIONS
Sildenafil, vardenafil, and tadalafil are safe and effective PDE5 inhibitors for the treatment of ED.
Setter
Stephen M
SM
Department of Pharmacotherapy, College of Pharmacy, Washington State University/Elder Services, Spokane, WA 99217-6131, USA. ssetter@smhca.org
Iltz
Jason L
JL
Fincham
Jack E
JE
Campbell
R Keith
RK
Baker
Danial E
DE
D015106:3',5'-Cyclic-GMP Phosphodiesterases; D002243:Carbolines / Q000009:adverse effects / Q000493:pharmacokinetics / Q000627:therapeutic use; D002986:Clinical Trials as Topic; D054706:Cyclic Nucleotide Phosphodiesterases, Type 5; D048909:Diabetes Complications / Q000150:complications; D004347:Drug Interactions; D007172:Erectile Dysfunction / Q000150:complications / Q000188:drug therapy* / Q000503:physiopathology; D006801:Humans; D007093:Imidazoles / Q000009:adverse effects / Q000493:pharmacokinetics / Q000627:therapeutic use; D008297:Male; D010726:Phosphodiesterase Inhibitors / Q000009:adverse effects / Q000493:pharmacokinetics / Q000627:therapeutic use*; D010727:Phosphoric Diester Hydrolases / Q000378:metabolism*; D010879:Piperazines / Q000009:adverse effects / Q000493:pharmacokinetics / Q000627:therapeutic use; D011183:Postoperative Complications / Q000188:drug therapy; D011468:Prostatectomy; D011687:Purines; D000068677:Sildenafil Citrate; D013450:Sulfones / Q000009:adverse effects / Q000493:pharmacokinetics / Q000627:therapeutic use; D000068581:Tadalafil; D014227:Triazines / Q000009:adverse effects / Q000493:pharmacokinetics / Q000627:therapeutic use; D000069058:Vardenafil Dihydrochloride
D002243:Carbolines; D007093:Imidazoles; D010726:Phosphodiesterase Inhibitors; D010879:Piperazines; D011687:Purines; D013450:Sulfones; D014227:Triazines; D000069058:Vardenafil Dihydrochloride; D000068581:Tadalafil; D000068677:Sildenafil Citrate; D010727:Phosphoric Diester Hydrolases; D015106:3',5'-Cyclic-GMP Phosphodiesterases; D054706:Cyclic Nucleotide Phosphodiesterases, Type 5; C517381:PDE5A protein, human