Erectile dysfunction is one of the most common sexual disorder among men, with about 150 million men worldwide. Until 1998, the treatments for this disorder were limited to surgery and natural remedies. After placing the first drug to combat erectile dysfunction, the pharmaceutical industry has improved the original formula and has perfected the drugs until current treatments. Cialis is a medicine made ​​from Tadalafil, a phosphodiesterase enzyme inhibitor. This chemical acts directly in the corpora cavernosa of the penis to allow the arrival and retention of more blood flow into the penis. This way, you get erections and lasting to keep full and satisfying sex.