For research and educational purposes only. Not medical advice.
Sildenafil Reference
Educational, not medical advice reference for Sildenafil: Sexual Health; regulatory status, evidence posture, source review, and schedule notes.…
Plain English
- What it is
- Sildenafil is a prescription pill best known by the brand name Viagra. It belongs to a group of medicines called PDE5 inhibitors. The exact same drug is also sold under the name Revatio to treat a type of high blood pressure in the lungs.
- What people use it for
- Doctors prescribe it mainly to help men get and keep an erection, a problem called erectile dysfunction. A lower-strength version is used for a rare lung condition called pulmonary arterial hypertension.
- What the science shows
- It is FDA-approved and has been tested in large human studies. It relaxes blood vessels and increases blood flow to the penis, but only when a person is sexually aroused. It does not create arousal on its own.
- The catch
- It can cause a dangerous drop in blood pressure if mixed with nitrate heart medicines, so that combination is off-limits. Common side effects are headache, facial flushing, upset stomach, stuffy nose, and short-lived blurry or blue-tinted vision. Any use outside a doctor's prescription is off-label and can be risky.
Reference summary
FDA-approved small-molecule PDE5 inhibitor with extensive human trial data. Labeled for erectile dysfunction (Viagra) and pulmonary arterial hypertension (Revatio and generic). It blocks PDE5 so cGMP accumulates in the corpus cavernosum, relaxing smooth muscle and increasing blood inflow, but only with sexual arousal. Onset is about 1 hour with a useful window of a few hours, shorter than tadalafil. Mechanism, dosing, contraindications, and adverse-event rates are established from the FDA label and peer-reviewed pharmacology reviews.
Regulatory and posture
- Categories
- Sexual Health
- Aliases
- Viagra, Revatio, sildenafil citrate, generic sildenafil, UK-92,480, little blue pill
- Evidence posture
- human - Labeled uses (ED, PAH) are backed by large human trials; pre-workout or general performance use is off-label.
- Regulatory status
- FDA-approved prescription medicine. Approved as Viagra for erectile dysfunction (1998) and as Revatio for pulmonary arterial hypertension (2005); the same molecule is sold as generic sildenafil. Uses beyond the two approved indications (for example a pre-workout pump or general performance) are off-label.
- Content review status
- label verified
Selected public sources
- VIAGRA (sildenafil citrate) Full Prescribing Information (ED indication, dosing, contraindications, adverse reactions)
- Sildenafil (generic) prescribing information: pulmonary arterial hypertension indication and dosing
- PDE5 inhibitors: pharmacology 20 years after sildenafil discovery (PK, nitrate warning)
- PDE5 inhibitors in the management of erectile dysfunction (onset, duration, adverse events)
Related tools
- Protocol builder overview - Public overview of the Pro protocol builder.