Site About Cialis Pills.

Viagra is a hugely successful drug, and other drug companies wanted a piece of the action. They developed different chemicals to block the PDE5 enzyme and created two new drugs: Cialis (tadalafil) and Levitra (vardenafil).

Because Cialis and Levitra block the PDE5 enzyme, they work exactly the same way as Viagra. They help men who have trouble maintaining an erection because of blood flow problems, and they only work when the man is sexually aroused.

Because they block PDE5 with different chemicals, however, there are some important differences between the three drugs. For example:

» Only Viagra causes color-vision problems.

» Cialis causes muscle aches in about 5 percent of patients.

» Viagra and Levitra last about four hours in the bloodstream. Cialis stays in the bloodstream much longer (it has a 17.5-hour half life) and can therefore be effective for more than a day.

Headache, stomach upset, back pain, muscle pain, nasal stuffiness, flushing, pain in arms or legs, dizziness, or vision changes may occur. If any of these effects persist or worsen, notify your doctor or pharmacist promptly.

Sexual activity may put extra strain on your heart, especially if you have heart problems. If you have heart problems or experience any of the following serious side effects during sex, stop and tell your doctor immediately of: severe dizziness, fainting, chest pain.

In the unlikely event you have a painful or prolonged erection (lasting more than 4 hours), stop using this drug and seek immediate medical attention or permanent problems could occur.

A serious allergic reaction to this drug is unlikely, but seek immediate medical attention if it occurs. Symptoms of a serious allergic reaction include: rash, itching, unusual swelling, severe dizziness, trouble breathing.

If you notice other effects not listed above, contact your doctor or pharmacist.

NOTES:
Do not share this medication with others, since they may have a problem that is not effectively treated by this drug, or they may have a condition that is complicated by this drug.

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%). Cialis’ mean half life is 17.5 hours in healthy men.

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 ( such as if you are on dialysis) because you may need a special dosage adjustment.

Likewise, if you try to obtain Cialis on the internet, please make sure that the person authorizing your prescription knows the true status of your liver function and your kidney function.

The BIG Discovery: cyclic guanosine monophosphate (cGMP)

Some very smart scientists discovered that cyclic guanosine monophosphate (cGMP) was the key to sustaining an erection.

They discovered that when a man gets sexually stimulated, a chain reaction occurs in the tissue of the penis that results in elevated levels of a substance called cyclic guanosine monophosphate (cGMP).

As long as there are sufficient levels of cGMP, the penis can remain erect. The more cGMP, the more robust and durable the erection.

If you inhibit the degradation of cGMP it stays around in the penis longer, producing a more durable erection.

Another way you can think of Cialis (and all other similar medicines) is that it preserves the elevated levels of cGMP that are created when a man is sexually stimulated for a stronger, more lasting erection.

That’s how Cialis works - 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 shouldn’t cause erections at inappropriate times because they only block degradation of cGMP produced in reaction to sexual stimulation, such as thinking about something sexy. If you are not being sexually stimulated, there is no cGMP to protect, so the drug remains in the background.