By now, there is little doubt that Viagra has become one of the most popular drugs of all time. And for many men, it is also the wonder drug of all time. These little blue pills have become so popular that it’s simply amazing.

For instance, on the search engine Google, there are over 17 million web pages that carry the word “Viagra” compared to a paltry 3.3 million that carry the word “aspirin” and an even lower 936,000 that carry the word “Tylenol”.

Television advertising for the drug comes in a constant and seemingly endless torrent of different visuals and messages, backed by a promotions budget reaching untold millions of dollars from the deep pockets of the drug’s manufacturer, Pfizer.

On its website, Pfizer makes the astounding claim that nine Viagra pills are dispensed every second, which is equivalent to close to 300 million tablets a year.

Even on the news, you can’t seem to get away from Viagra. Media outlets were buzzing last June 30 about the news that shock-jock Rush Limbaugh was arrested by police at the Palm Beach International Airport for having a bottle of Viagra in his possession that was prescribed to someone else.

The origins of Viagra (sildenafil citrate) are the stuff of folklore by now. Originally invented as a heart medication, Viagra failed in its original purpose but it gained worldwide notoriety when users discovered its unusual side effect of causing erections in males. Soon enough, Pfizer decided to market it for erectile dysfunction rather than for angina. The drug was subsequently approved by the FDA in 1998, making it the first pill approved to treat erectile dysfunction in the United States. A year later, it was offered for sale. Its commercial success was immediate. From 1999 to 2001, annual sales of Viagra consistently exceeded $1 billion.

While sildenafil is only available through a doctor’s prescription, it has been advertised directly to American consumers on television in those now-famous commercials featuring Bob Dole. Several sites on the internet also offer Viagra online. Viagra has become so popular that there are now aphrodisiacs that promote themselves as “herbal Viagra” while others imitate the drug’s shape and color. Viagra has also a roster of popular nicknames, such as Vitamin V, the Blue Pill and others.

However, despite its widespread popularity, there are still many who wonder how Viagra works. Let’s take a second look at the mechanics involved, in the simplest way possible.

When it comes to practically any kind of movement, your muscles are the key. When you want to move a part of your body, you think about that part and your muscles contract, causing that part of your body to move. But here’s where things get tricky. There are no muscle contractions involved when the penis gets erect. The penis uses pressure instead of muscles.

Think about a balloon. A balloon without air is limp and, if you put air into it, it becomes elongated and rigid. That’s how the penis works. But instead of pressurized air, the penis uses pressurized blood.

Still using the balloon as an example, erectile dysfunction occurs when the mouth of the balloon does not open up properly and air cannot get in. It’s like a piece of string was tied to a limp balloon preventing air from getting in.

In the penis, this piece of string is an artery and it tightens around the mouth of the balloon because of “smooth muscles” which tend to tense up involuntarily. When the smooth muscles are tense, the artery tightens around the penis preventing blood from rushing in. That’s erectile dysfunction. And that’s where Viagra does its work -- by simply relaxing those smooth muscles in order to let the blood flow to the penis and make it erect.