How to evaluate the efficacy of the phosphodiesterase type 5 inhibitors.
BACKGROUND
Several methods have been so far proposed to compare the effectiveness of the three available phosphodiesterase type 5 inhibitors (PDE5Is).


METHODS
Two urologists (E.C. and G.B.B.), together with the Controversy's Editor (E.A.J.), with expertise in the area of medical treatment of erectile dysfunction (ED) present the various perspectives on the evaluation of PDE5Is in ED. The use of the most popular psychometric tool, the International Index of Erectile Function, is presented by an expert psychologist (L.R.D.).


METHODS
Expert opinion supported by the critical review of the currently available literature.


RESULTS
Trials have demonstrated that the PDE5Is are excellent drugs with a great specificity of action and an almost perfect tolerance profile. Some instruments for comparison of clinical efficacy have to be considered subjective (psychometry, patient's preference, changes in quality of general, or sexual life). Some others are more objective (hardness, hormonal levels, and local circulation). An evidence-based comparison of the three PDE5Is should in the future be rooted in both subjective and objective methods. This will be of paramount importance in the drug trial design of new, forthcoming PDE5Is.


CONCLUSIONS
Comparison between PDE5Is using both subjective and objective parameters will permit to individuate, on the basis of the evidence, the subset of couples where one drug, or one dose, or dose regimen, is to be considered of first choice.
Course of Endocrinology and Medical Sexology, Department of Experimental Medicine, University of L'Aquila, L'Aquila, Italy. emmanuele.jannini@univaq.it
Emmanuele A
EA
Jannini
Leonard R
LR
DeRogatis
Eric
E
Chung
Gerald B
GB
Brock
D002243:Carbolines / Q000627:therapeutic use; D007172:Erectile Dysfunction / Q000188:drug therapy*; D006801:Humans; D007093:Imidazoles / Q000627:therapeutic use; D008297:Male; D010410:Penile Erection / Q000187:drug effects; D058986:Phosphodiesterase 5 Inhibitors / Q000627:therapeutic use*; D010879:Piperazines / Q000627:therapeutic use; D011687:Purines / Q000627:therapeutic use; D000068677:Sildenafil Citrate; D013450:Sulfones / Q000627:therapeutic use; D000068581:Tadalafil; D016896:Treatment Outcome; D014227:Triazines / Q000627:therapeutic use; D000069058:Vardenafil Dihydrochloride
D002243:Carbolines; D007093:Imidazoles; D058986:Phosphodiesterase 5 Inhibitors; D010879:Piperazines; D011687:Purines; D013450:Sulfones; D014227:Triazines; D000069058:Vardenafil Dihydrochloride; D000068581:Tadalafil; D000068677:Sildenafil Citrate