Erectile DYsfunction / Sildenafil Citrate

Sildenafil citrate

Sildenafil is the generic form of the brand Viagra®. Both medications work similarly in the body.

Viagra® is a type of medication known as a PDE5 inhibitor that is used to treat erectile dysfunction. It comes in several different doses and is taken as-needed.

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Disclaimer: The information provided on this page is not a substitute for professional medical advice, diagnosis, or treatment. If you have any questions or concerns about your health, please talk to a doctor.

Transparent manufacturing

Sildenafil manufactured by Greenstone in France.


Sildenafil should be taken without food 30-60 minutes before sex and its effects last up to 6-8 hours.

Serious side effects include an erection lasting more than 4 hours, sudden vision loss in one or both eyes, and sudden hearing decrease or loss. If these occur, seek medical attention immediately.

Talk to your doctor or nurse practitioner about your medical conditions and your medications before taking sildenafil. Do not take sildenafil if you are allergic to its ingredients or if you are already taking nitrates (such as nitroglycerin), street drugs called “poppers” (such as amyl nitrate, amyl nitrite, butyl nitrate), or guanylate cyclase stimulators (such as riociguat).

What is sildenafil citrate?

Sildenafil citrate is the chemical name of the active ingredient in Viagra®. When sildenafil is sold in 25, 50, or 100 mg dosages, it's called Viagra or it is the generic for Viagra. When it is sold in a 20 mg dosage, it is called Revatio or it is the generic for Revatio. Revatio is FDA approved for treating pulmonary hypertension. Both Viagra and Revatio contain the exact same ingredient (i.e., sildenafil citrate), they simply differ in the strength in which they are produced. Healthcare professionals on the Dapper platform have the discretion to prescribe 20 mg sildenafil citrate tablets for ED in doses ranging between 20 mg and 100 mg if they believe that it is an appropriate course of treatment for a particular patient. Sildenafil citrate 20 mg tablets for ED is an off-label usage of the medication. It is up to the medical judgment of the doctor or nurse practitioner to decide if off-label treatment is appropriate for a patient based on his unique medical history, symptoms, and preferences. The Dapper Pharmacy Network is able to fill prescriptions for sildenafil citrate 20 mg tablets that are issued by a healthcare professional on the Dapper platform.

Does Dapper offer genuine Viagra?

Dapper offers genuine, branded Viagra® and generic Viagra® to treat erectile dysfunction (ED) in 25, 50, or 100 mg dosages. Dapper also offers sildenafil citrate in 20 mg tablets, which can be prescribed by doctors off-label to treat ED in doses ranging between 20 mg and 100 mg if they find it medically appropriate to do so. The active ingredient, sildenafil citrate, is identical in both medications.

How should I take sildenafil?

Sildenafil should be taken 30-60 minutes before sex. It's important to take it without a meal because fat in a meal can decrease and delay its absorption, which can lower sildenafil's effectiveness. Even though the instructions are to take it 30-60 minutes before sex, sildenafil lasts in the body for up to 6-8 hours.

How long does sildenafil take to work?

Sildenafil is a short acting medication with a rapid onset. It should be taken 30-60 minutes before sex, and it reaches peak blood levels in 60 minutes on average. Fat in a meal can delay the effects of sildenafil and also decrease the amount that is absorbed. Remember that sildenafil will not give you a spontaneous erection without sexual stimulation.

How long does sildenafil last?

Sildenafil is a short acting drug with an average half-life of 4-5 hours, which means that half the medicine is gone from the body after 4-5 hours in healthy people. The time that it takes to eliminate sildenafil may be prolonged in older people and people with liver or kidney disease and the drug may work longer in these people.

Can sildenafil have permanent effects?

Sildenafil does not have permanent effects on the body once it is broken down. It is only effective for as long as it is in the body. Sildenafil does not have permanent effects on the body once it is broken down. It is only effective for as long as it is in the body.

As you age, it is normal to see erectile function decrease. As a result, you may need more medication to see the same results. In some cases, erectile function may also worsen due to progression of the underlying disease that is causing ED (e.g., diabetes, vascular disease).

Sildenafil does not diminish in efficacy over time (i.e., you don't need more because your body gets “used to it”).

What should I tell my doctor?

Tell your doctor or nurse practitioner if you have any problems with your heart, liver, kidneys, vision disorders, bleeding disorders, or penile deformities. Tell your doctor or nurse practitioner about all prescription medications, over the counter medications, and dietary supplements you are taking. For more safety information, please see the important safety information below.

Common side effects of sildenafil

The most common side effects of sildenafil include headaches, facial flushing, stuffy nose, and upset stomach. Serious side effects that are rare include an erection that will not resolve even after 3-4 hours (priapism), hearing loss, which can be sudden, and vision loss in one or both eyes. For more information about side effects, see sildenafil side effects below.

What happens if I overdose?

Taking more than the recommended amount of sildenafil citrate greatly increases your risk of side effects, including severe ones that can be dangerous, such as severe low blood pressure or an erection that won't go away even after 4 or more hours (priapism). Never take more than the amount prescribed to you by your doctor or nurse practitioner. If you have any severe side effects after taking more than the recommended amount, or even after taking the amount of medicine prescribed to you, seek out emergency medical attention immediately.

Is buying sildenafil online safe?

Buying medication online can have risks when the source is not reputable. One 0%-200+% of the drug. In cases where the active ingredient is present in lower amounts than expected, this can mean lack of effectiveness even though the same dose of active drug may work well in a given individual. In cases where much more active drug than listed is included, there is a higher potential for side effects, including dangerous ones like extremely low blood pressure or an erection that won't go away even after 4 or more hours (priapism). It is also common for counterfeit drugs to contain harmful ingredients like talcum powder, commercial paint, and printer ink.

With Dapper, you can always be sure you are getting genuine medication with active ingredients in the correct amount without harmful additives. Dapper drugs are manufactured by pharmaceutical companies that are regulated by the FDA. In fact you will likely find many of the same manufacturers we use in your local pharmacy. With Dapper, you never need to worry about what's actually in the pills you are taking.

Important safety information