Sildenafil 20 mg: what it is for
Sildenafil 20 mg is a prescription tablet strength labeled for pulmonary arterial hypertension, not typical ED dosing. Review safety and interactions.
Key facts
- Sildenafil is $69.67/month (billed $209 every 90 days), charged only after a clinician approves it.
- Answer a few health questions online. A licensed clinician reviews them. If approved, it ships to your door.
- Adults 18 or older. A licensed clinician reviews your health history and decides whether treatment is appropriate for you. Availability depends on the state you live in.
Sildenafil 20 mg is a prescription tablet strength most closely associated with Revatio, which is FDA-approved for pulmonary arterial hypertension (PAH). You may also see 20 mg tablets prescribed off-label in sexual health care, but the FDA-labeled erectile dysfunction product (Viagra) uses different tablet strengths. This page explains what “sildenafil 20 mg” usually means, key safety issues, and what to ask your prescriber. Vitals Vault also offers PocketMD, a free AI health companion for questions grounded in your own history.
- Sildenafil 20 mg is labeled for pulmonary arterial hypertension, not typical erectile dysfunction dosing.
- Do not use sildenafil with nitrates or riociguat due to dangerous low blood pressure.
- Common side effects include headache, flushing, indigestion, and nasal congestion.
- Sudden vision or hearing loss, chest pain, fainting, or priapism need urgent evaluation.
What is sildenafil 20 mg used for?
Sildenafil 20 mg tablet details (label-based)
- Drug class
- Phosphodiesterase type 5 (PDE5) inhibitor. (Revatio and Viagra prescribing information)
- FDA-approved use for 20 mg tablets
- Pulmonary arterial hypertension (PAH) (Revatio). (Revatio prescribing information)
- How it works (plain language)
- Increases cyclic GMP by inhibiting PDE5, which can relax blood vessels. (Revatio and Viagra prescribing information)
- Key interaction to know
- Contraindicated with nitrates and with riociguat due to hypotension risk. (Revatio and Viagra prescribing information)
Why 20 mg exists
Sildenafil is marketed in different strengths depending on the FDA-approved indication. The 20 mg tablet strength corresponds to Revatio, which is labeled for PAH. Viagra is labeled for ED and uses different tablet strengths.
ED use can be off-label
Some clinicians prescribe sildenafil 20 mg tablets off-label for ED, sometimes to allow flexible dosing using multiple tablets. Off-label prescribing can be appropriate, but it should be based on your health history and other medications.
Do not combine with nitrates
Taking sildenafil with nitrates (for example, nitroglycerin products used for chest pain) can cause a dangerous drop in blood pressure. This is a strict contraindication in FDA labeling. Tell every clinician who prescribes you medications that you take sildenafil.
Also avoid riociguat
Sildenafil is contraindicated with riociguat, a medicine used for certain types of pulmonary hypertension. The combination can cause significant low blood pressure. If you are treated for pulmonary hypertension, your specialist should coordinate all related medications.
Common side effects
Commonly reported side effects in labeling include headache, flushing, indigestion (dyspepsia), nasal congestion, and dizziness. Some people notice visual color tinge or blurred vision. If side effects are bothersome, discuss options with your prescriber rather than adjusting on your own.
Serious symptoms to act on
Seek urgent care for chest pain, fainting, or severe dizziness, especially during sexual activity. Get urgent evaluation for sudden vision loss or sudden hearing decrease or loss. An erection lasting more than 4 hours (priapism) is an emergency to prevent permanent injury.
| Product name | Typical labeled use | Common tablet strengths listed | Where 20 mg fits |
|---|---|---|---|
| Revatio (sildenafil) | Pulmonary arterial hypertension (PAH) | 20 mg (tablet) | This is the labeled tablet strength |
| Viagra (sildenafil citrate) | Erectile dysfunction (ED) | 25 mg, 50 mg, 100 mg (tablet) | 20 mg is not a labeled Viagra strength |
When to talk to a clinician about sildenafil
You take heart medicines
Tell your clinician if you use nitrates (for chest pain) or riociguat, because sildenafil is contraindicated with both. Also share any alpha-blocker use, since combining blood pressure lowering medicines can increase dizziness or fainting risk.
You have chest pain with sex
Chest pain, shortness of breath, or fainting during sexual activity needs medical evaluation. Do not treat this as a dosing problem. ED can sometimes be an early sign of cardiovascular disease, so it is worth a broader health review.
You have eye or ear symptoms
Sudden vision loss or sudden hearing decrease or loss requires urgent evaluation. If you have certain eye conditions or a history of vision problems, ask whether a PDE5 inhibitor is appropriate for you.
You have liver or kidney disease
Reduced liver or kidney function can change how your body processes sildenafil. Your prescriber may choose a different approach or closer monitoring. Bring a full medication list, including over-the-counter products and supplements.
Pro tips for safer use
Keep a current med list
Bring all prescriptions and as-needed meds, especially nitrates.
Ask what your tablet is for
Confirm whether sildenafil 20 mg is for PAH or off-label ED.
Know emergency symptoms
Chest pain, fainting, sudden vision or hearing changes, or priapism need urgent care.
Mention blood pressure issues
Lightheadedness can be worse with antihypertensives or alpha-blockers.
Avoid mixing ED drugs
Do not combine PDE5 inhibitors unless your clinician directs it.
Frequently Asked Questions
What is sildenafil 20 mg used for?
Sildenafil 20 mg tablets are FDA-approved for pulmonary arterial hypertension (PAH) under the brand Revatio. For erectile dysfunction, sildenafil is FDA-approved as Viagra in different tablet strengths, so 20 mg is typically used only if prescribed off-label.
What is a sildenafil 20 mg tablet?
A sildenafil 20 mg tablet is one strength of sildenafil, most commonly associated with Revatio for PAH. The same active ingredient is used in Viagra for ED, but the labeled tablet strengths for Viagra are different.
Can I take sildenafil 20 mg with nitroglycerin?
No. Sildenafil is contraindicated with nitrates such as nitroglycerin because the combination can cause a dangerous drop in blood pressure. If you have chest pain and might need nitrates, tell your clinician you use sildenafil.
Is sildenafil 20 mg the same as Viagra?
They contain the same active ingredient (sildenafil), but they are labeled for different uses and come in different tablet strengths. Revatio is labeled for PAH and includes a 20 mg tablet; Viagra is labeled for ED and uses other strengths.
What are the most common side effects of sildenafil 20 mg?
Common side effects in labeling include headache, flushing, indigestion, nasal congestion, dizziness, and visual changes. Seek urgent evaluation for chest pain, fainting, sudden vision loss, sudden hearing decrease or loss, or an erection lasting more than 4 hours.