Sildenafil (Viagra), Vardenafil (Levitra) and Tadalafil (Cialis) or three tools from erectile dysfunction, mechanism of action which do not differ from each other.

Meanwhile, for promotional purposes the manufacturers of each drug argue that it is better than others. If earlier, in the first advertising campaign Viagra, shot an elderly Senator Bob Dole, now clips heroes become men no older than forty.

How does it work?

All three medications belong to the group of phosphodiesterase inhibitors fifth type (PDE5). This is an enzyme that inhibits vasodilation of the penis, and thus weakens erection. Viagra and Levitra are very similar in structure and properties, and the structure of Cialis is somewhat different.

But in practice the main difference between drugs is that one of them (Levitra) is absorbed faster, and the other (Cialis) is displayed. That is, the effect of all blockers, PDE-5 is essentially the same, but differ in time of onset and duration.

The first such drugs were getting really sick impotence people. According to prescription sexual life is able to establish to those suffering from diabetes, neurological disorders or side effects of antidepressants.

But later the demand for Viagra increased sharply. First, doctors were no questions asked to prescribe to all who asked. Second, there were numerous online pharmacies that offered the impotence drugs without a prescription and delivery.

Accordingly, the expanded range of buyers. Patients become healthy people who wanted to be safe before exciting date.

Simply put, Viagra, Levitra and Cialis are now buying all who want to be confident in their sexual opportunities, regardless of the circumstances. Manufacturers of drugs at the same time emphasize that eating or alcohol does not affect their effectiveness.

Sex In The City

Can you try to recreate a collective image of the consumer of these "playful" drugs? According to psychologists, the need for viagra and its analogues is primarily diagnosed in residents of large cities. The sexual revolution has led to that increasingly sexual contacts occur between strangers: colleagues, met at a party or an ad on the Internet.

In the minds of most people it is the image of the ideal man, always ready for sex and willing thereof. Trying to match this view, men take pills secretly.

A portrait of one of these consumers is described in the New York Times. 41-year-old Chris London lives in new York and worked as a lawyer. One of his business partners once said that might not normally work with a man, if before they had sex. London was smaller least discouraged by this statement, but agreed to meet after work. On the advice of the doctor his excitement, he won a Viagra, quietly swallowed in the bathroom.

Entering the bedroom with rosy cheeks (a common side effect of Viagra) these men complained about the heat and stuffiness. And in the morning often hide as suffer from headaches – a very common side effect of taking inhibitors PDE-5.

As noted by The New York Times, such tablets often drink and gay men. Both lovers are doing it secretly from each other, and then together experiencing the same side effects.

The last but not the least

All three drugs are effective in about 80% of cases. From them Levitra acts in very low doses 5-10 times less than the competition. This slightly reduces the severity of side effects, but in diseases of the cardiovascular system after a stroke and the drug is still contraindicated.

And about the side effects of all three drugs besides the desired enzyme PDE5, block other. For example, Viagra and Levitra act on the enzyme PDE-6, which is responsible for color sensation. And Cialis inhibits the activity of PDE-11 in the heart, the thymus gland or the brain. But what undesirable consequences it brings, is not yet known.

Another interesting aspect — the interaction of these drugs with food and alcohol. It is known that fasting Viagra works much faster than when eating. However, though slowly, the effect is still coming. As for alcohol, Cialis, as stated in the brochures, does not interact with it — unlike its competitors. Levitra is also safe in combination with alcohol, but alcohol abuse is one of the most frequent causes of impotence.

In the end

If you read the scientific definition of "impotence", it becomes clear that this is repeated inability to maintain an erection necessary for sexual intercourse. Hence it is clear that Viagra, and its analogs act exclusively on the blood supply to the penis and have no psychotropic effects. That is, these drugs can improve potency but do not stimulate libido. Although, as found out by psychologists, some men with normal erection the desire of sex often comes by itself.