Cialis blocks the enzyme phosphodiesterase-5 (PDE5) which is responsible for the neutralization of cGMP. Cialis (Tadalafil) is a highly selective inhibitor of PDE5. (PDE5 is not the only phosphodiesterase involved in the erectile physiology but it appears to be the most important one). The nice thing about PDE5 blockers is that they don't cause erections at inappropriate times because they only block degradation of cGMP produced in reaction to sexual stimulation.



Cialis is readily absorbed from the bloodstream. It is about 16% bioavailable. Tadalafil is about 94% bound to plasma protein. Cialis can be taken from 30 minutes to 12 hours prior to sexual activity and remains active for upto 24 hrs. Cialis also claims to have fewer side effects such as facial flushing that comes over some men when they take< a href=http://www.getmedix.com/mens_health/viagra.php> Viagra.

Cialis have side effects like headache, flushing, indigestion, urinary tract infection, nasal congestion and dizziness. And both should not be given to men taking Nitrates in any form. There are more serious side effects and therefore a proper consultation is required before starting these drugs

Cialis is mostly metabolized in the liver by an enzyme known as CYP3A4 and to a lesser extent CYPC2. Tadalafil breakdown products are excreted in the feces (61%) and in the urine (36%). If you are going to take any of the PDE5 inhibitors such as Cialis, it is very important that your doctor be aware if you have a liver condition (such as cirrhosis) or kidney condition as you may need a special dosage adjustment.

And if you buy Cialis online, please make sure that the person authorizing your prescription knows the true status of your liver function and your kidney function or asks for your doctor's prescription.

Cialis should not be used without doctors? prescription and a thorough checkup is required before you can take Cialis safely.