Viagra is the most well-known therapy for erectile dysfunction or ED. When it was approved by the FDA in 1998, it became the first safe oral treatment for erection problems. It completely changed the way this condition is treated today and remains a sought-after choice. It enhances levels of nitric oxide in the body and this natural chemical works with other enzymes to relax and expand blood vessels. Consequently, blood flow improves leading to better erectile function. ... Read more