Development of Cialis was undertaken by the drug company Icos as early as 1993, though it took 10 years to gain approval for this medication.

At the beginning, Icos was conducting tests on a PDE5 inhibitor called IC351. The way that erectile dysfunction drugs work is by inhibiting PDE5, which is an enzyme. In doing so, blood flow to the penis is increased.

But, at the time that these tests were underway, Icos did not understand the link that it might have to the treatment of erectile dysfunction, and it can only be assumed that they were testing IC351 for a different reason.

Patents and clinical trials

In 1994, Icos received its first patent for IC351. This was the same year that Viagra-manufacturer Pfizer discovered that the drug they were testing on heart patients actually caused an erection in these individuals.

The next year, Icos began their first phase of clinical trials. In 1997, during phase II of clinical studies, the drug company first began using IC351 in patients who were suffering from erectile dysfunction.

Icos then decided to partner with another drug company, Eli Lilly and Co., in 1998 to commercialize IC351 for the purpose of treating men with sexual dysfunction problems. In 2000, the joint company now called Lilly Icos, LLC, applied to the FDA for approval of this new medication, and at this time they decided to rename it Cialis.

Benefit of Cialis compared to Viagra

In 2002, Phase III test results were presented to the American Urological Assocation. Lilly and Icos reported that Cialis would stay in the system and continue working for up to 36 hours. This is one of its distinct advantages it has over Viagra, which normally remains effective in the body for only four hours.

This long-lasting impact has earned it the nickname: ?The Weekend Pill?, or ?Le Weekend? in France.

And, unlike Viagra, which takes about an hour to start working, Cialis kicks in 30 minutes after consumption, and it can be taken on a full stomach without diminishing its effectiveness.

In November of that year, Cialis was approved in Europe, but the FDA did not approve it in America until one year later. By this time, it was already available in 50 countries worldwide.

Cialis pills, which come in doses of 5mg, 10mg, and 20mg, are yellow, film-coated and almond-shaped. It is the third approved drug for the treatment of impotence, after Viagra and Levitra. Normally, the starting dose is 10mg, after which it may be adjusted according to how the medication affects a particular individual.

Alternative uses of Cialis

Scientists have also engaged in a clinical development program to determine whether it would be safe for men to take Cialis on a regular, once-daily basis. This would help men avoid the hassle of having to plan sexual activity in coordination with the consumption of the pill. This type of daily usage was approved in low dosages ? either 2.5mg or 5 mg by the European Commission in June 2007.

Currently, Tadalafil ? the generic name for Cialis, is undergoing tests to see whether it could be used to treat pulmonary arterial hypertension as well, due to its special, long-lasting properties.

Possible side effects

Some common side effects discovered with the use of Cialis are: headache, back pain, indigestion, flushing and runny nose. You should always consult with a doctor, who will also discuss with you how to buy Cialis.