Addyi online

Medication features of interest include efficacy in terms of quality of erection, consistency of effects, rapid onset of action, long duration of action, side?effect profile and route of administration; drug costs have to be considered, too, if the medicinal product is flibanserin buy online not reimbursed [ 1 ]. Three PDE5 inhibitors are currently commercially available; each one is characterized by particular pharmacokinetic features.

In the attempt to evaluate which is the most favoured drug, several preference studies have been conducted in the last few years. Unfortunately, several of them have proved to be severely flawed because of methodological pitfalls. Mulhall [ 4 ] made the point that patient preference studies are not the same as the classical efficacy and safety studies, and set forth detailed recommendations for their conduct. The ideal study for preference evaluation should: (i) be randomized, double?blind, crossover; (ii) not include bias by pre?selection of patients (e.g.

only nonresponders to previous treatment); (iii) make fair comparisons, adopting equivalent doses of each drug and giving each drug for equal periods; (iv) be based on an intent?to?treat analysis. He also indicated several pitfalls: drug instructions might differ considerably, e.g.

because of differences in duration of action, and invalidate the blinding, or might even condition patient preference; period effects might produce improvements over time that

bias

He also raised the issue of how patient preference should be assessed. A single question, such as ‘Which

treatment

The aim of this review is to establish whether current knowledge enables any conclusive judgement. We electronically searched Medline (from 1966 to 2007 week 18) and EMBASE (from 1988 to 2007 week 18) using the search string ‘(tadalafil or vardenafil) AND Sildenafil AND clinical trial AND erectile dysfunction’ combined with ‘drug preference OR drug choice OR patient preference OR patient attitude OR patient satisfaction’ and limited to articles in English and referring to humans. The studies identified were stringently assessed according to the Mulhall criteria. We identified seven patient?preference studies (Table 1) [ 5-12 ], comprising six interventional trials [ 5-10, 12 ] and one observational trial [ 11 ]. All of them compared tadalafil with sildenafil, generic sildenafil online addyi viagra 25 mg tablet buy online online except two, i.e. a large double?blind study by Rubio?Aurioles et al. [ 10 ] that compared vardenafil with sildenafil, and a small open?label study by Tolra et al. [ 9 ] that compared sildenafil with vardenafil and tadalafil.

Three of the studies were declared as sponsored by Lilly ICOS LLC [ 7, 8, 11 ] and one jointly by Bayer and Glaxo?SmithKline [ 10 ]. Ref Design Population, n inclusion criteria Treatment Questionnaires [ 5 ] Randomized, double?blind Crossover Fixed dose 1–2 week washout SIL vs TAD 191 completers 18–65 years ?3 months ED Heterosexual TAD naive SIL naive/insufficient therapy SIL 50 mg 30 min up to 4 h before sex TAD 20 mg 30 min up to 24 h before sex ?4 weeks TP question SEP diary TEAE [ 6 ] Open?label, fixed dose, 1?way cross over, 1?week screening3?week SIL assess 1 week treatment?free washout 6?week TAD initiation 3?week TAD assess 6?month extension 147 completers ?18 years ?3?month history of ED on SIL treatment at stable dose for 6–24 weeks Stable heterosexual relationship SIL continue 25–100 mg as before (100 mg max 35%) TAD 20 mg % choosing TAD for extension SEP diary TEAE [ 7 ] Randomized, Double?blind, crossover 4?armed study drug preference TAD – SIL or SIL – TAD DIP TAD – SIL (drug was always TAD) Drug comparison, 219 Instructions comparison, 46 18–65

years

TAD