Cialis is one of the famous ED pills available in the market. The generic form of the drug is Tadalafil while Cialis is only the brand name. The path of ED pills in the market has been opened by the discovery and the efficient use of the Sildenafil drug. Since then many companies have come up with different ED medicines. But not all could be efficient. A French pharmaceutical manufacture company called Eli Lily and Company is the manufacturer of these little opal shaped pills. The U.S. Department of Food and Drug Administration (FDA) has given approval to this pill way back in 2003. The only feature that makes this pill different from any other erectile dysfunction pills is that the effective time of this pill is 36 hours which is the longest effective time any ED pill can give. This is the reason why this pill is also referred to as a " weekend pill ". How does Cialis work? The working mechanism of Cialis is exactly life any other ED pills. This medicine finds i...