This oral medication works by increasing the blood flow to the penile region after due sexual stimulation.  Cialis relaxes the muscles around the penis and ensures that adequate blood flows to the requisite areas of the body. Scientifically known as a PDE5 inhibitor group of drugs,  Cialis works in the same way as other drugs of the same genre. The basic point of difference is the main molecule contained in each of these medicines, which lend its typical attributes to the brand. The two other important brands which fall in this category are Viagra and Levitra.

Cialis is available only when backed by a doctor prescription. This is because,  Cialis ought to be taken under medical supervision and under recommendations from a doctor. The doctor is the best guide to assess whether you are medically suitable to consume the drug and whether your current medications would indeed allow you to go for  Cialis therapy. Some of the warnings for  Cialis users are as follows:

1.    This drug should not be taken in combination with drugs containing nitrates, which are usually prescribed for chest pain or heart ailments. If taken in combination it might cause severe drop in blood pressure which can lead to fainting, stroke or even a fatal heart attack.
2.    You must tell your doctor if you have have a past history of some diseases including, heart beat problems, recent history of a heart attach, stroke or heart failure, chest pain, high or low blood pressure, liver or kidney ailments, stomach ulcers and more.
Cialis contains Tadalafil and if you are allergic to its ingredients, you should not take the medication. The drug is available in 3 strengths: 5, 10 and 20 mg. The dosage should not exceed more than one tablet per day. The tablets are almond shaped and you ought to allow 24 hours to pass between the intake of two consecutive tablets. The effect of the drug lasts for 36 hours and its onset of action is within 30 minutes. Hence do not expect an erection, soon after taking  Cialis.
 
Some of of the common side effects when you buy cialis are feeling of warmth or redness of the neck, face and chest; stuffy or runny nose; headache; stomach upset; changes in vision; light-headed feeling; painful erection which lasts more than 4 hours, and more. In case you find yourself suffering from any of these or any other side effect, do talk to your doctor immediately. The other factor which must be reported to the doctor is if your erection remains more than 4 hours and the penis does not return to its usual flaccid state. This is a serious medical condition called priapism and demands immediate medical intervention.   

Few of the reasons why men prefer  Cialis over other drugs of the same genre: The effect of the drug starts within 30 minutes of ingestion and its effects last in the body for 36 hours. This enables men not to any forward planning before their sexual activity. This is a great relief for most men. The other good reason why men prefer  Cialis over other drugs is that it is available in lower strengths compared to other drugs. Thus, men can start with lower doses of  Cialis and gradually progress to higher doses, if advised by the doctor.