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Erectile function, erection hardness and tolerability in men treated with sildenafil 100 mg vs. 50 mg for erectile
M Kirby1, D L Creanga, V J Stecher
1The Centre for Research in Primary and Community Care (CRIPACC), University of Hertfordshire, Hatfield, Herts, UK.
Aim:
To compare efficacy and tolerability between 100-mg and 50-mg sildenafil doses in five double-blind, placebo-controlled (DBPC) fixed-dose studies.
Methods:
Doses were compared for the change (baseline to end of 8-12 weeks of DBPC treatment) in score on the Erectile Function (EF) domain of the International Index of Erectile Function (IIEF; from five fixed-dose studies, > 1500 men); the per-patient estimated percentage of occasions that a specified Erection Hardness Score (EHS; from two of the five fixed-dose studies, > 500 men) was achieved, computed from logistic regression; the odds ratio (OR) of achieving EHS3 (hard enough for penetration, but not completely hard) and EHS4 (fully hard and completely rigid); and the adverse event incidence by treatment (from all five fixed-dose studies).
Results:
For the 100-mg vs. 50-mg dose, IIEF-EF score improvement was consistently greater across the five studies and was statistically significant when data from two studies with similar design were pooled (10.7 ± 0.64 vs. 8.9 ± 0.83, p = 0.0287); and during the first 2 weeks of treatment, the odds of achieving EHS4 erections were almost doubled in one study (OR = 1.77, p = 0.0398). Sildenafil was generally well tolerated at either dose.
Conclusion:
Men with erectile dysfunction treated with 100-mg compared with 50-mg sildenafil may be more likely to achieve a greater improvement in erectile function and, within the first 2 weeks, completely hard and fully rigid erections, with little or no greater risk to tolerability.
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