How It Works
Cialis and other impotency drugs for erectile dysfunction; their fundamentals for functioning are same but 
what distinguish Cialis from rest of the squad is its fascinating ability of its effect to last longer than any other impotency drug, which is up to 36 hours, that is 17.5 hours half-life in comparison to the number one impotency drug for erectile dysfunction Viagra having 4 hours of half life time. This earned Cialis the name of “Weekend Pill” and unlike others it can also be taken as once a daily.
The erection of penis and its rigidness during sexual stimulation is the direct result of the increased flow of blood through chambers corpora cavernosa; one for inflow and other for outflow that causes the loss of erection. This accumulation of blood is caused due the relaxation of muscles of corpora cavernosa that is implemented through the occurrence of certain chemical reactions where the nerve terminal releases Nitric Oxide and endothelial cells, which provides the enabling environment to inhibit the enzyme and thus the muscles remain relaxed and the accumulated blood does not exit through the outflow chamber of corpora cavernosa. Now what Cialis does is that it inhibits the enzymes that are responsible to make the corpora cavernosa muscles to contract and let the out flow of blood from the penis possible by not letting the chemical reaction to occur.