TruDataRX Insights

The story of the “Little Blue Pill”

Bethany Sneathen and Dr. James Stahl

Once upon a time in 1989, scientists at Pfizer began development of a substance called sildenafil. They hoped the drug, which dilates blood vessels, would be useful for high blood pressure and chest pain associated with heart disease. Early clinical trials were disappointing, except for one happy little surprise discovered by a particularly observant nurse: Whenever she and the other nurses entered the room to check on the clinical trial participants, they would find the men lying on their stomachs, trying to hide their erections.1 Sildenafil was indeed working to dilate blood vessels, just not quite where the scientists had anticipated.

Following this discovery, attention shifted away from the treatment of cardiovascular conditions, as the scientists at Pfizer realized they actually had on their hands a treatment for erectile dysfunction. This strategy of using a known drug to treat a new condition for which it was not originally intended is known as “drug repositioning,” and is quite common in the drug development process. Sildenafil, of course, soon became Viagra (sildenafil), which was approved by the FDA in 1998. The subsequent media attention soon made the “Little Blue Pill” a household name. Competition arose in the form of several similar drugs, including Cialis, Levitra, and Stendra, starting in 2003.

The cardiovascular effects of sildenafil were not forgotten, and development of sildenafil for certain cardiovascular conditions continued quietly until it was approved for the treatment of pulmonary arterial hypertension in 2005 under the alias Revatio (sildenafil). Why give it a new name? Well, if you’re taking Revatio for pulmonary arterial hypertension, you take a 20 mg pill three times a day – there’s no extra benefit from taking more than that.2 But Viagra is only available in 25 mg, 50 mg, or 100 mg pills. So the only difference between Revatio (sildenafil) and Viagra (sildenafil) is which dose is available.

Why worry about Revatio at all? Well, Revatio went generic in 2012, and is now available for less than $1 per pill.3 In contrast, a generic for Viagra came out in 2017, but the lowest price for this drug (with a coupon) still comes to about $20 per pill (and competitors like Cialis are still over $50 per pill)!4,5 But if it’s exactly the same substance, can’t you just take generic Revatio instead of Viagra? You’ll be taking a slightly different dose, but the Viagra drug label does specifically say “Based on effectiveness and toleration, the dose may be increased to a maximum recommended dose of 100 mg or decreased to 25 mg.”6 Accordingly, there’s no reason not to treat erectile dysfunction with 2 to 5 generic Revatio pills (40 mg to 100 mg), instead of with generic Viagra or its competitors. For a payer with dozens of members taking an erectile dysfunction drug, this is a very stiff cost difference.


  1. Foley, KE (2017). Viagra’s famously surprising origin story is actually a pretty common way to find new drugs. Quartz. Accessed April 24, 2018.
  2. Food and Drug Administration (2018). Revatio Label. ID: 4215617, p2
  3. Revatio Coupons on GoodRx. Accessed April 24, 2018.
  4. Viagra Coupons on GoodRx. Accessed April 24, 2018.
  5. Cialis Coupons on GoodRx. Accessed April 24, 2018.
  6. Food and Drug Administration (2017). Viagra Label. ID: 4194824, p2