In 1998 doctors concealed that sildenafil citrate led to erections in subjects who were were volunteers in a medical study that had been planned to study another indication for this substance. Since then, Pfizer Generic Viagra has been the drug substance more taken by patients who have undergone erectile dysfunction. Why can Pfizer generic viagra be thought as the best sildenafil? Because it was the first medication that showed men the chance of being sexually happy again. And this matter is essential for sildenafil citrate makers. Pfizer generic viagra comes in three amounts and all of them can be proper. It will depend on each consumer’s medical condition. Physicians trust Pfizer generic viagra so they can advise it confidentially and give their patients the best direction. If you have erectile dysfunction, do not be sad. This medication has been waiting for for you since 1998.