The history of Cialis cannot be discussed without mentioning Pfizer's drug, Viagra (sildenafil). The FDA's approval of Viagra was a groundbreaking event for the treatment of erectile dysfunction and sales eventually reached over a billion dollars. The FDA subsequently approved Levitra and Cialis (tadalafil). It is an orally administered drug used to treat male erectile dysfunction. It is a yellow, film coated, almond shaped tablets. Generic Cialis is available at drugstores at a very affordable prices. This drug really is a big help to ageing men who generally encounters such problem. Thus, even generic it would help men out there who has problems with their erection and impotence—their common problem.