After the discovery of sildenafil and the enormous success in the treatment of erectile dysfunction, the most important companies in the pharmaceutical market were at a great disadvantage compared to Pfizer, a company that marketed Viagra; consequently, they have assiduously undertaken the search for new and more effective phosphodiesterase type 5 inhibitor drugs, a category to which sildenafil belongs.
Vardenafil is a phosphodiesterase type 5 inhibitor used to treat erectile dysfunction.
History of vardenafil
Vardenafil is the second phosphodiesterase type 5 inhibitor drug to have been marketed after obtaining authorization from the Food and Drug Administration for the treatment of erectile dysfunction on August 19, 2003.
Vardenafil was marketed at the same time by the three pharmaceutical companies that designed it - Bayer Pharmaceuticals, GlaxoSmithKline and Schering-Plow - under the registered name of Levitra ®. In 2005, however, the company Bayer Pharmeceutical has taken the rights to commercialize the vardenafil under the name of Levitra in the markets outside the United States, then in Italy as well as in other European Union countries, to the pharmaceutical company GlaxoSmithKline. Today, the pharmaceutical company GlaxoSmithKline sells vardenafil under the registered name of Vivanza ®.
Due to the EU trade laws, which allow parallel amounts, vardenafil in Italy and other EU member countries can be found on the market under both registered names, namely Levitra (sold by Bayer Pharmaceuticals) and Vivanza (sold by GlaxoSmithKline). Recently, an orodispersible form of vardenafil has been approved in the United States of America and Canada, which is marketed under the registered name of Staxyn ®.
Vardenafil, more than the result of a real research or a scientific discovery, is a structural modification of the parent molecule, sildenafil (viagra active ingredient). In fact, the chemical structure of vardenafil differs from that of sildenafil only due to the different position of a nitrogen atom and the alkyl substituent of the piperazine ring, which instead of being a methyl group, is an ethyl group, ie it was added only a carbon atom that absolutely does not change the pharmacokinetic and pharmacodynamic properties of vardenafil compared to sildenafil. It can indeed be noted that the pharmacological properties, the side effects, the time it takes for the drug to take effect and other characteristics of vardenafil are very similar to those of sildenafil. However, despite all the similarities, vardenafil has a particular property, which no other phosphodiesterase type 5 inhibitor possesses; vardenafil significantly increases the time it takes from the start of vaginal penetration to ejaculation and can therefore also be used in the treatment of premature ejaculation . This advantage of vardenafil can be used to treat patients suffering from both erectile dysfunction and premature ejaculation with a single drug.
Action mechanism
To function, vardenafil needs sufficient sexual stimulation, otherwise its intake does not produce the desired effect.
Vardenafil is a phosphodiesterase type 5 inhibitor (PED5), specific for cGMP (cyclic guanosine monophosphate); type 5 phosphodiesterase is mainly located in the smooth muscle of vessels of the corpus cavernosum of the penis and is the enzyme responsible for the degradation of cGMP (cyclic guanosine monophosphate); therefore the inhibition of this enzyme by vardenafil leads to a higher concentration of cGMP (cyclic guanosine monophosphate), consequently it allows a greater vasodilation giving a more vigorous erection through the greater supply of blood in the corpus cavernosum.
In conclusion we can say that vardenafil, being a phosphodiesterase type 5 inhibitor specific for cGMP (cyclic guanosine monophosphate), does not have a direct relaxing effect, but effectively increases the muscle relaxant effect of nitric oxide (NO) on the smooth muscles of the cavernous body of the penis: when the NO / cGMP pathway is activated, as happens during sexual stimulation, the inhibition of phosphodiesterase of type 5 by vardenafil considerably increases the level of cGMP in the cavernous body.
Also vardenafil, like the other phosphodiesterase inhibitor drugs of type 5 and the treatments of erectile dysfunction in general, has conquered all the internet pages, most of which offers a very simple way to get the drug, even offering to send the drug directly to the home of the customer concerned. Many people are attracted by the possibility of obtaining vardenafil via the internet, seduced by seemingly low prices and by the desire to solve their problem without contacting their doctor, thus avoiding possible embarrassment. This is obviously an absolutely wrong attitude, because the doctor is indispensable in the evaluation of the problem. For example, erectile dysfunction can be different in nature and medication not necessary.
Often vardenafil and other inhibitors of the enzyme phosphodiesterase type 5 are sold in much lower or higher doses than the recommended therapeutic ones, and / or in preparations that combine multiple '' miraculous '' drugs: similar cocktails are advertised by the managers of these internet sites as "very powerful" or "infallible"; in reality similar doses can seriously harm the health of the patient by increasing the extent and incidence of the side effects of the drug. Therefore, the purchase of vardenafil via the internet without first consulting with a doctor is strongly discouraged. In case of intake of vardenafil by people who are older or who have cardiovascular disorders, it is also necessary to carry out a thorough and preventive medical assessment to ensure that the administration of vardenafil does not lead to any serious side effects and does not interfere with the clinical picture of the patient.
