The little blue pill is Viagra, the brand name for a medication called sildenafil. It was the first oral treatment for erectile dysfunction (ED) approved by the FDA, on March 27, 1998. The nickname comes from its distinctive appearance: a blue, diamond-shaped, film-coated tablet stamped with “Pfizer” on one side and a dosage code on the other.
What Viagra Looks Like
Authentic Viagra tablets are blue, rounded-diamond-shaped pills available in three strengths: 25 mg, 50 mg, and 100 mg. Each tablet is debossed with “PFIZER” on one side and “VGR25,” “VGR50,” or “VGR100” on the other, corresponding to the dose. The blue color and diamond shape became so iconic that “the little blue pill” entered everyday language almost immediately after the drug launched.
How It Works
Sildenafil works by blocking an enzyme that normally breaks down a chemical messenger involved in relaxing blood vessel walls. When that messenger builds up in the smooth muscle tissue of the penis, blood vessels widen, blood flow increases, and an erection becomes possible. The drug doesn’t create arousal on its own. It makes the body’s natural response to arousal more effective.
Most men find it works within about an hour of taking it. In clinical studies, 97% of patients achieved erections sufficient for intercourse one hour after dosing, and 74% still had a clinical effect 12 hours later. The standard starting dose is 50 mg, taken as needed roughly an hour before sexual activity, though this can be adjusted up to 100 mg or down to 25 mg depending on how well it works and how well it’s tolerated.
Common Side Effects
The most frequently reported side effects are headache, facial flushing, upset stomach, nasal congestion, and changes in color vision (some people notice a temporary blue tint). Back pain, muscle pain, dizziness, and nausea can also occur. These effects are generally mild and short-lived.
Rare but serious reactions include priapism, an erection lasting more than four hours that requires emergency treatment. Sudden hearing loss (sometimes with ringing in the ears) and sudden vision loss in one or both eyes have also been reported in rare cases.
Who Should Not Take It
The most dangerous interaction is with nitrate medications, which are commonly prescribed for chest pain (angina). Combining sildenafil with nitrates can cause a sudden, severe drop in blood pressure that may lead to fainting, heart attack, or stroke. Recreational drugs known as “poppers” (amyl nitrate or butyl nitrate) carry the same risk. Medications used to treat enlarged prostate, called alpha-blockers, can also interact and may need dose adjustments.
Heart attacks, strokes, and irregular heartbeats have been reported rarely in men taking sildenafil, though most of those men had pre-existing heart conditions. The drug lowers blood pressure slightly on its own, so anyone with cardiovascular concerns should have that conversation with their prescriber before starting it.
Generic Sildenafil vs. Brand-Name Viagra
Generic sildenafil became available after Pfizer’s patent exclusivity ended, and the price difference is dramatic. Brand-name Viagra has carried a list price above $60 per pill, while generic sildenafil has dropped to under a dollar per dose in many pharmacies. The active ingredient is identical. Between late 2017 and mid-2021, the average list price for a common generic prescription (six tablets of 100 mg) fell by 98%, from $265 to about $4. Over the same period, brand-name Viagra prices actually increased by 27%.
Because of this gap, the vast majority of prescriptions today are filled with generic sildenafil rather than brand-name Viagra. Both come in the same three strengths and work the same way. The generic tablets may not always be blue or diamond-shaped, since those design elements were specific to Pfizer’s branding, but the medication inside is chemically equivalent.