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Sildenafil treats erectile dysfunction (ED) and is the active ingredient in Viagra. In this article, we look at how sildenafil works for ED, other uses, and the best places to buy it online.
This article discusses sildenafil, an ED drug, and how it works to relieve the condition.
Sildenafil is the generic version of the brand-name drug Viagra and a popular treatment for ED. Those with this condition have difficulty getting or maintaining an erection. ED is a widespread condition, though many people find it difficult to discuss.
The main ingredient in sildenafil is sildenafil citrate. The inactive ingredients include:
- microcrystalline cellulose
- anhydrous dibasic calcium phosphate
- croscarmellose sodium
- magnesium stearate
- hypromellose
- titanium dioxide
- lactose
- triacetin
- artificial colors
Viagra is just one brand name drug containing sildenafil. This and other brand-name drugs containing sildenafil as an active ingredient will typically have inactive ingredients that differ, making them unique to that brand.
Another brand-name medication containing sildenafil is Revatio, which also treats a condition called pulmonary hypertension.
A person cannot get sildenafil without a valid prescription from a doctor or prescribing healthcare professional in the United States.
Sildenafil comes in tablet form and is available in strengths of 25, 50, and 100 milligrams (mg). It also comes in 20-mg doses as the generic form of Revatio, but it does not have Food and Drug Administration (FDA) approval for treating ED.
People generally take a 50-mg sildenafil tablet approximately
Sildenafil is fast-acting, and its effects typically last up to 4 hours. However, the drug does not instantaneously produce an erection, and sexual arousal is necessary for the drug to work. Sildenafil also does not affect a person’s sex drive or libido.
Sildenafil may take longer to work if a person takes it with food. It is best to take the drug on an empty stomach. People can swallow sildenafil tablets with water.
Sildenafil belongs to a class of medications called phosphodiesterase type 5 (PDE5) inhibitors. These inhibit phosphodiesterase enzymes, which degrade the molecules that relax the muscle tissue. This allows for more relaxed penile muscles and increased blood flow, causing an erection.
Though sildenafil does not cure ED, it can help treat the symptoms of the condition.
People are
A person with symptoms of ED can try taking sildenafil if they first discuss it with a healthcare professional to ensure it is suitable. If appropriate, a doctor will provide a prescription.
The United Kingdom’s National Health Service (NHS) states that most males over the age of 18 can take sildenafil for ED.
ED may sometimes signify an underlying health issue, so sildenafil may help treat some symptoms in individuals with certain conditions.
Some people with the following conditions may take sildenafil for treating ED:
- type 2 diabetes
- multiple sclerosis
- heart disease
- high blood pressure
- atherosclerosis, which refers to the hardening of the arteries
Learn more about the causes of ED.
Sildenafil for pulmonary hypertension
People with
According to the NHS, most children over 1 year and adults can take sildenafil for this pulmonary hypertension. The FDA recommends adults take 20 mg of sildenafil three times daily for this condition, with a 4- to 6-hour gap between doses.
A person always needs to seek a doctor’s guidance and recommendations when taking sildenafil for pulmonary hypertension.
Learn more about the use of sildenafil for pulmonary hypertension.
People
A person cannot take sildenafil if they have hypersensitivity to any ingredient in the drug. Other people who cannot take sildenafil include those with:
- Pulmonary veno-occlusion: This involves the blockage of oxygen-carrying blood vessels from the lungs to the heart due to fiber buildup in small veins.
- Left ventricular outflow obstruction: This refers to a heart condition that stops blood flow from the left heart ventricle.
- Pulmonary arterial hypertension with sickle cell anemia: This refers to high blood pressure in the lungs with irregularly shaped red blood cells.
- Multiple system atrophy: This is a rare condition that causes damage to the nerve cells in the brain over time.
Sildenafil can negatively interact with some medications, hindering their effectiveness or causing side effects.
Some types of medication a person should not take alongside sildenafil include:
- Nitrates: Combing nitrates and sildenafil can cause very low blood pressure levels. This includes street drugs containing nitrates known as poppers.
- Blood pressure medications: Taking blood pressure medications and sildenafil together can significantly reduce blood pressure levels.
- Other PDE5 inhibitors: Taking sildenafil with another PDE5 inhibitor can increase the risk of side effects.
If a person is taking or plans to take any other medications, they must speak with a doctor before taking sildenafil. They should also mention to a doctor any vitamins, supplements, or herbal products that they take or plan to take before taking this medication.
Below, we highlight the full range of side effects of sildenafil, from common to serious side effects that will need immediate medical attention.
Common side effects of sildenafil
Some common side effects of sildenafil include:
- headaches
- flushing
- indigestion (dyspepsia)
- vision changes
- nausea
- dizziness
- rashes
- nasal congestion
- back pain
Serious side effects of sildenafil
Serious side effects of sildenafil include:
- sudden and severe vision loss
- blurry vision
- loss of hearing
- ringing in the ears (tinnitus)
- dizziness
- fainting
- chest pain
- shortness of breath that worsens
- an erection that is painful and lasts longer than 4 hours (priapism)
- symptoms of an allergic reaction, such as:
Anyone using sildenafil who experiences these side effects should seek immediate medical attention.
Sildenafil dietary interactions
Consuming fruit juices such as grapefruit, pomegranate, Seville orange, and pomelo may
Combining sildenafil with alcohol can also cause interactions. A
- indigestion
- skin rash
- headaches
- facial flushing
- chest discomfort and palpitations
- dizziness
- altered vision
- nasal congestion
What to do
If a person has taken too much sildenafil and has difficulty breathing, is unconscious, or has a seizure, they or someone near them should call emergency services at 911 immediately.
Otherwise, a person can call America’s Poison Centers for emergency attention at 1-800-222-1222 or visit the Poison Help website.
A sign of a sildenafil overdose is an increase in the severity and duration of common side effects. Another indicator of a sildenafil overdose is vision changes,
There
People can use telehealth companies to buy sildenafil online. They often need to answer health questions and have an online appointment with a doctor before they can get a prescription. Below, we look at the best places to buy sildenafil online.
Risk of counterfeit ED medications
A person should ensure they carry out detailed research before purchasing ED medications online, as they are among the
The table below compares the telehealth companies offering sildenafil and Viagra.
We selected these telehealth services based on criteria we think are good indicators of safety, quality, and transparency.
As a part of our vetting process, we consider:
- a product’s composition, ingredients, and overall quality
- any third-party certifications
- a company’s reputation and business practices
- any lab test results
- marketing claims
Read more about how we vet products and brands.
Yes, sildenafil is as strong as Viagra. They both contain the same active ingredient.
Sildenafil can work for up to 4 hours. However, it does not stop an erection from going down after ejaculation. A study from 2005 suggested that sildenafil can reduce the amount of time a person waits to develop another erection after ejaculation, but more recent studies have not confirmed this.
Sildenafil is a PDE5 inhibitor that increases blood flow to the penis to help someone develop an erection. It does not cure erectile dysfunction it can help a person manage the condition.
People need to avoid using sildenafil if they are also taking nitrate medications. This is because both of these medications lower blood pressure. Taking sildenafil and nitrate medications together can make blood pressure dangerously low.
Sildenafil takes up to 1 hour to work.
Sildenafil is the generic version of the brand name drug Viagra. It is an effective erectile dysfunction (ED) drug available at a fraction of the cost of Viagra.
Sildenafil is just as safe and effective as Viagra. However, as with Viagra, it carries the risk of potential side effects and drug interactions.
People who experience ED need to discuss their treatment options with a doctor before taking any medications.