Sildenafil: what it is, how it works, and safety
Sildenafil treats erectile dysfunction and pulmonary arterial hypertension. Learn how it works, who should avoid it, and the side effects to know.
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.
- A $20 clinician review, refunded if you don’t qualify.
Sildenafil is a prescription tablet best known for treating erectile dysfunction (ED). It is also used under different dosing for pulmonary arterial hypertension (PAH), a type of high blood pressure in the lungs. This page explains what sildenafil is, who it may fit, key safety issues like nitrate interactions, and what affects cost and access. If you are considering treatment, Vitals Vault can connect you with clinician reviewed care options where available.
- Sildenafil is a prescription medicine used for erectile dysfunction and pulmonary arterial hypertension.
- It works by helping blood vessels relax, which can increase blood flow during sexual stimulation.
- Do not use sildenafil with nitrates or riociguat because blood pressure can drop dangerously.
- Common side effects include headache, flushing, indigestion, and nasal congestion.
- Seek urgent care for chest pain, sudden vision or hearing loss, or an erection lasting over 4 hours.
What sildenafil is
A PDE5 inhibitor
Sildenafil belongs to a drug class called phosphodiesterase type 5 (PDE5) inhibitors. These medicines affect blood vessel tone and blood flow. Sildenafil is prescription only and is taken by mouth as a tablet.
Used for ED
Sildenafil is FDA approved to treat erectile dysfunction, which is difficulty getting or keeping an erection firm enough for sex. It does not increase sexual desire. It helps the body respond to sexual stimulation.
Also used for PAH
Sildenafil is also FDA approved for pulmonary arterial hypertension (PAH) under the brand name Revatio. PAH treatment uses different dosing and goals than ED treatment. Do not assume the same regimen applies across conditions.
Generic and brand names
Sildenafil is the generic name of the active ingredient. Viagra is a brand name product that contains sildenafil for ED. Revatio is a brand name product that contains sildenafil for PAH.
How sildenafil works for erections
Boosts a natural signal
During sexual stimulation, your body releases nitric oxide in penile tissue. This increases a messenger called cyclic GMP (cGMP), which helps smooth muscle relax and allows more blood to flow in. Sildenafil helps by slowing the breakdown of cGMP.
Requires sexual stimulation
Sildenafil does not cause an automatic erection. It supports the normal erection pathway, so sexual stimulation is still needed. If ED is related to stress, relationship factors, or certain medical conditions, results can vary.
Also relaxes lung vessels in PAH
In PAH, sildenafil can help relax blood vessels in the lungs and improve exercise ability. PAH is a serious condition that needs specialist care. If you are taking sildenafil for PAH, follow your PAH prescriber’s instructions.
- Drug class
- Phosphodiesterase type 5 (PDE5) inhibitor.
- How it is taken
- By mouth as a tablet (oral).
- Why interactions matter
- It can lower blood pressure, especially with nitrates or riociguat.
Who sildenafil is for
Adults with ED
Sildenafil is commonly prescribed for adult men with erectile dysfunction. ED can have physical causes, psychological causes, or both. A clinician can help check for contributing factors such as diabetes, high blood pressure, medication side effects, or low testosterone.
People with PAH
Sildenafil is also prescribed for pulmonary arterial hypertension, typically by clinicians experienced in PAH care. The goals are different from ED treatment, such as improving exercise tolerance. Do not switch between ED and PAH products without clinician guidance.
People who want an as-needed option
Some people prefer an as-needed ED medication rather than a daily option. A clinician may discuss how sildenafil compares with other PDE5 inhibitors, including how long effects may last and how side effects feel for you.
Those who can safely tolerate BP effects
Because sildenafil can lower blood pressure, it tends to fit best when your cardiovascular status and medication list make that drop safe. If you have heart disease or take multiple blood pressure medicines, a clinician should review your risks carefully.
Who should not take sildenafil
Anyone using nitrates
Do not take sildenafil if you use nitrates for chest pain, such as nitroglycerin (tablets, spray, patches, or ointment) or isosorbide products. The combination can cause a severe drop in blood pressure. Tell emergency clinicians you have taken sildenafil if you have chest pain.
Anyone using riociguat
Do not take sildenafil with riociguat, a medicine used for certain types of pulmonary hypertension. Using them together can lower blood pressure too much. A prescriber should choose one approach based on your condition.
Severe allergy to sildenafil
Do not take sildenafil if you have had an allergic reaction to sildenafil or any ingredient in the product. Signs can include rash, swelling, or trouble breathing. Seek urgent care for symptoms of a severe allergic reaction.
Certain heart conditions need caution
Some people should avoid sexual activity or ED medicines due to cardiovascular risk, such as unstable angina or severe heart failure. Your clinician may need to assess whether sexual activity is safe for you before prescribing any ED treatment.
What to expect when you take sildenafil
Timing varies by person
How quickly sildenafil works and how long it lasts can vary based on your dose, your metabolism, and what you have eaten. The FDA label notes that a high fat meal can delay the time to peak levels. If you want help choosing timing, discuss it with your prescriber.
You may need a few attempts
Some people do not get the desired effect the first time, especially if anxiety, alcohol, or relationship stress is involved. A clinician may review technique factors like adequate stimulation, and medical factors like diabetes or medication interactions. Do not change your dose on your own.
Blood pressure effects are expected
Sildenafil can cause a temporary lowering of blood pressure. This is why interactions with nitrates and certain other medicines are so important. If you feel faint, dizzy, or have chest pain, seek medical help.
ED treatment is not one-size-fits-all
If sildenafil does not work well or side effects are bothersome, other options exist, including other PDE5 inhibitors and non-pill treatments. A clinician can help match the option to your health history and preferences. Do not combine ED medicines unless a clinician specifically directs it.
Sildenafil side effects and warnings
Headache
Headache is one of the most common side effects. It is related to blood vessel widening. If headaches are frequent or severe, your clinician may reassess whether sildenafil is a good fit or whether another ED option might be better.
Flushing and warmth
You may notice facial flushing or a warm sensation. This is usually temporary and related to blood vessel effects. If flushing comes with chest pain, fainting, or severe dizziness, seek urgent evaluation.
Indigestion and nausea
Some people have upset stomach or indigestion. Taking sildenafil exactly as prescribed and reviewing food effects with your clinician can help. Persistent vomiting, black stools, or severe abdominal pain needs medical attention.
Nasal congestion
A stuffy nose can occur because blood vessels in the nasal passages relax. This is usually mild. If you have significant shortness of breath or wheezing, seek care because that is not a typical congestion symptom.
Sudden vision or hearing loss
Rarely, people report sudden decrease or loss of vision or sudden decrease or loss of hearing, sometimes with ringing in the ears or dizziness. Stop sexual activity and seek urgent medical care if this happens. Your clinician will advise whether you should avoid PDE5 inhibitors in the future.
Priapism (erection over 4 hours)
An erection that lasts more than 4 hours is a medical emergency because it can damage penile tissue. Seek emergency care right away if this occurs. Risk may be higher in people with certain blood disorders or penile anatomy conditions.
Cost and access
What drives sildenafil cost
Sildenafil cost depends on whether you use a brand product or an FDA approved generic, your dose and quantity, and where you fill the prescription. Pharmacy pricing and discount programs can vary widely. Current prices for the Vitals Vault option are shown on this page in the price block.
Insurance coverage varies
Some insurance plans cover sildenafil for ED, some cover it only for PAH, and others may not cover ED medicines at all. Plans may require prior authorization or limit quantities. Your clinician or pharmacist can help you understand what your plan allows.
Prescription required
Sildenafil is a prescription medication, so you need a clinician evaluation to confirm it is safe with your health history and other medicines. Avoid buying sildenafil pills from unverified online sources, which can be counterfeit or contain the wrong dose. A legitimate pharmacy will require a prescription.
Access through telehealth
Telehealth can be a convenient way to discuss ED, review your medication list, and get a prescription when appropriate. A licensed clinician should screen for contraindications like nitrates and assess cardiovascular safety. Availability of telehealth prescribing depends on your state.
How to get sildenafil safely
- 1
Review your health history
Make a list of your medical conditions, heart history, and all medicines, especially nitrates and alpha blockers.
- 2
Complete a clinician evaluation
A licensed clinician reviews your symptoms, risk factors, and medication list to decide if sildenafil is appropriate.
- 3
Discuss options and monitoring
If prescribed, ask about expected effects, side effects, and when to follow up if it is not working or causes problems.
- 4
Fill through a legitimate pharmacy
Use a pharmacy that requires a prescription and can answer questions about your sildenafil tablet and interactions.
Frequently Asked Questions
Who makes Viagra?
Viagra is a brand name sildenafil product made by Pfizer. Many other manufacturers make FDA approved generic sildenafil tablets. Your pharmacist can tell you which manufacturer supplied your specific prescription.
What is a sildenafil pill used for?
Sildenafil is used to treat erectile dysfunction and, under different dosing, pulmonary arterial hypertension. For ED, it helps the body respond to sexual stimulation by improving blood flow. It does not increase sexual desire.
Is sildenafil generic?
Yes. Sildenafil is the generic name of the active ingredient in Viagra (for ED) and Revatio (for PAH). Generic sildenafil products are FDA approved and must meet quality and bioequivalence standards.
Can I buy sildenafil near me without a prescription?
In the US, sildenafil is prescription only, so a legitimate pharmacy will require a prescription. Be cautious with unverified online sellers because counterfeit ED medicines are common. A clinician can help confirm it is safe with your medications.
Is sildenafil cost shown on this page?
If you are looking for sildenafil cost, the current prices for the Vitals Vault option are shown on this page in the price block. Your out of pocket cost can still vary based on pharmacy, quantity, and insurance coverage. A pharmacist can explain your final price at checkout.