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Safety of Prescribing PDE-5 Inhibitors via e-Medicine vs Traditional Medicine


      To determine the safety of a US-based, state-regulated Internet system vs a multispecialty primary care system for prescribing phosphodiesterase type 5 (PDE-5) inhibitors for erectile dysfunction.


      From January 1, 2001, through December 31, 2005, 500 e-medicine clients (mean ± SD age, 47±11 years; hypertension, 60%; type 2 diabetes mellitus, 2%; mean ± SD number of medications, 0.4±0.8) vs 500 traditional medicine patients (mean ± SD age, 57±12 years; hypertension, 50%; type 2 diabetes mellitus, 23%; mean ± SD number of medications, 5.1±3.1) with erectile dysfunction symptoms were assessed. Noninferiority safety was assessed in this retrospective, cross-sectional study with stratified random sampling by identification of prescribing in the presence of clinically important PDE-5 inhibitor drug interactions with or without high-risk cardiovascular disease, by asking about diagnostic symptoms specific to erectile dysfunction, and by determining frequency of patient counseling.


      Noninferiority of the e-medicine system was shown for the 6 safety end points, relative to a traditional medicine system. Numbers of inappropriate prescriptions, after correction for disease and medication covariates, did not differ between systems. Medication counseling showed superiority of the e-medicine system. Standard diagnostic questions were required for e-medicine prescribing but were infrequently asked in traditional medicine.


      Safety in prescribing PDE-5 inhibitors for erectile dysfunction was similar between a US-based, state-regulated Internet prescribing system and a multispecialty primary care system.
      CI (confidence interval), IIEQ (International Index of Erectile Questions), PDE-5 (phosphodiesterase type 5), RR (relative risk)
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