Pharmacological Properties of Viagra
Viagra is a PDE5 Inhibitor. This treatment works by blocking the activity of cGMP which had been preventing the muscles in the arteries of the penis from relaxing. Once these muscles are relaxed, the user is able to develop and maintain an erection. The drug was initially intended to reduce blood pressure in those suffering angina, but was found to have no significant impact in this area. Its potential for was discovered incidentally.
Viagra is available in a choice of doses – 25, 50 and 100 milligrams – with the patient's appropriate dosage determined by a GP or medical professional.
The active agent in Viagra is 'sildenafil citrate', a drug also on the market as Revatio. Other popular PDE5 Inhibitors include Cialis and Levitra, but Viagra was the first to be approved by the relevant government agency.
Viagra was developed by Pfizer in the 1990s and took the world by storm! Sales hit $1 billion in its first two years on the market, and there are now thousands of retailers and chemists trading in the drug. Viagra is prescribed in the US and in the UK , but can be purchased online without any medical consultation. If choosing the latter route, it is worth bearing in mind that there are hundreds of 'herbal remedies' available named after the drug and, when choosing online, these are not always easy to spot.