Viagra chemical name is sildenafil citrate and is the most commonly prescribed medication for erectile dysfunction in men. Originally named as UK92480, it was discovered accidentally by scientists working at Pfizer laboratories when they were working on sildenafil as a cardiovascular drug to lower blood pressure. They were testing the drugs on volunteers and found out that those people did not want to discontinue the use of drug because erections were harder, firmer and lasted longer. The subjects reported that they enjoyed sex a lot since they are trying this new drug.
It was approved by US FDA on March 27, 1998 and have since changed the life of millions of men and women around the world. Before the drug came to the market millions of men around the world were highly disappointed because there was no oral treatment for erectile dysfunction. The only treatment was penile injections or prosthetic implant.
The total sale of Viagra in 2015 was 1708 million US dollars. It is estimated that 50% of men over the age of 50 have some kind of impotence and they need viagra to get and keep an erection.
It is available as 25mg, 50 mg and 100 mg tablets. The most common dose is 50 mg,needs to be taken orally at-least half an hour before the sexual act and the effect lasts for about 4 hours. The dose can be increased to 100 mg or reduced to 25 mg.The absorption is very delayed if Viagra is consumed after a fatty meal. Multiple side effects can occur when you take viagra, notable among them are dizziness, headache, flushing and stomach upset. Some patients also have complaints regarding blurred vision, increased sensitivity to light and distinguishing between blue and green color.
Before a patient is put on Viagra,a detailed medical history should be asked and a physical examination undertaken. A detailed history of heart problem,irregular heart beat, allergy,fainting and dizziness, low blood pressure should be asked by the physician. It is also advised not to drive or be near machinery that can cause problems due to dizziness. Patients are also advised to limit the alcohol consumption while on drug.
Sildenafil interacts with many drugs and a detailed drug history is warranted before starting it. It specifically interacts synergistically with Nitrates, alpha blockers resulting in low blood pressure and fainting. Some other drugs like antifungals, macrolide antibiotics and some antiviral affect the rate of clearance of the drug from the body.
Prolonged erection and priapism has been commonly reported in many post-marketing studies. If anything like this happens the patient should immediately report to ER to prevent permanent damage to the penile tissue.
Viagra is not indicated in women and no studies exist for prescribing viagra in pregnant or lactating women.
Viagra is a prescription medicine , but in Australia it can be purchased online too. It does not come with the brand name ‘Viagra’ but it is freely available in generic form. It can be easily ordered online so that patients can maintain the secrecy. If you search, several sites will come up that deliver Viagra or generic sildenafil to your doorsteps.