Sildenafil 20 mg: Is It the Right Dose for ED?

Reviewed by Mary Lucas, RN

Written by Our Editorial Team

Updated 09/11/2021

Everything about your penis doesn’t have to be about size, but we will admit that the right dose of sildenafil or any other ED medication is very important. 

Erectile dysfunction (ED) is a frustrating condition for the many men who deal with it on a regular basis, and despite the medical tests and lectures a healthcare provider may put you through to get a prescription, a lot of guys aren’t well educated on how sildenafil dosages work. 

For instance, some men may search online until they find the biggest dosage — or the smallest drug concentration — and think that’s what they need, all without talking to a healthcare professional. 

Sexual intercourse is great, but it’s not worth dying for. So what about a just-right middle dosage? Is 20 mg of sildenafil the right way to address your ED? 

Here’s what’s helpful to know about the sildenafil 20 mg dose. 

Because while sildenafil 20 mg is an ideal single dose strength for some situations and some people, it may or may not be the right dose for you.

What Is Sildenafil? 

Sildenafil is the other name for the ED medication’s original prescription treatment: Viagra®. You’ve likely heard of it!

Sildenafil is the generic version of a phosphodiesterase type 5 (PDE5) inhibitor. These medications work to sustain dilation of your blood vessels — therefore improving blood flow to and within your penis. (This ideally results in better and firmer erections for you in the process, and in turn, better sexual activity). 

Not all PDE5 inhibitors are the same, however. For instance, Tadalafil (Cialis®) can work for a day or more, but sildenafil is best taken as a sort of pre-game erectile dysfunction solution. When you’re ready to get to “business,” you take sildenafil, which in an appropriate dosage will prepare you for better action for the next few hours, according to the National Library of Medicine.

Research shows that men with ED can see many benefits from sildenafil. In fact, more than 90 percent of men respond well to PDE5 inhibitors. 

But those results depend largely on the cause of your erectile dysfunction, which may be different than another man’s. 

The best results with medications like sildenafil occur in men with “no identifiable organic cause” to their ED, and these men may see a 90 percent success rate with treatment. 

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Why Sildenafil Dosages Can Vary

The big question you’re probably asking is why there are so many different dosage sizes within the sildenafil world. 

With a range from 5mg to 100 mg on the market, it would be fair to assume that the low end might be ineffective for any use, and the high end might be generally considered dangerous, right? 

Well, not exactly. Sildenafil may offer more precise or noticeable benefits at higher doses, but it depends greatly on what you’re actually treating with sildenafil. 

For instance, a 2017 study found a higher general frequency of erections for someone taking 100 mg of sildenafil daily vs. 50 mg daily. 

The effect was that men with ED using the higher dosage experienced more frequent erections during the trial period.

However, there are benefits to both ends of the dosage spectrum.

The Standard Sildenafil Dosages: Benefits in Brief

You may already know this, but there is a health benefit and safety threshold with these pills, which you may or may not want to consider when it comes to sexual activity. 

The effects of sildenafil will take between 30 and 60 minutes to activate once consumed, and will last for around four hours.

According to the FDA, sildenafil doses can range between 25mg and 100 mg for ED.

Side effects of too much sildenafil can be scary. Adverse effects can include a sudden decrease or drop in blood pressure, blurred vision and shortness of breath, and more serious side effects of Viagra and sildenafil overdose can include chest pain and heart attack. 

If your dose of sildenafil causes any of these problems, contact a healthcare professional immediately, and discontinue any further doses of sildenafil treatment at any concentration.

So where does 20 mg sildenafil come in? Surprisingly, it has little to do with your penis. 

Sildenafil is commonly prescribed at 20 mg not to treat erectile dysfunction (or any other sexual dysfunction disorder for that matter). 

Instead, it’s FDA-approved at this dosage to address a medical condition called pulmonary hypertension.

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Is 20 mg Sildenafil the Perfect Dose?

Pulmonary arterial hypertension is a serious blood pressure condition that can lead to serious health problems including pulmonary veno-occlusive disease (a condition in which the small blood vessels that carry blood from the lungs to the heart become blocked) and other heart problems if not treated. 

It’s a significant concern for people with existing hypertension and blood pressure issues, and taking a 20 mg dose (or lower, in some cases) of sildenafil has been shown to be effective in treating this type of disease.

Sildenafil 20 mg is not a commonly prescribed dose for erectile dysfunction — which is not to say, however, that it can’t be effective in certain circumstances

It may be the perfect dose for a healthcare professional to test for adverse reactions or sensitivity to the treatment, rather than starting you at a 100 mg dose, which can come with those side effects worth worrying about. 

Some common side effects of sildenafil might include headaches or dizziness, or you might develop an allergic reaction, like a rash. 

Some men experience a sudden decrease in blood pressure, as mentioned above. 

Significant blood pressure drops can sometimes cause death, so don’t mix sildenafil with other blood pressure medications without first consulting with your healthcare provider.

ED medications also have a unique side effect to be mindful of: erections that last for several hours, due to a condition called “priapism.” 

These longer-than-normal erection sessions can cause permanent damage if not treated, so seek medical attention if your erection lingers for more than a few hours.

Note: Something which could cause major problems: a double dose. Don’t do it.

A double dose of sildenafil won’t give you twice the benefits, because PDE-5 inhibitors simply create the proper conditions for erection — but they might not give you an erection if your ED has psychological origins, for instance. 

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Sildenafil Doses: Talk to Your Healthcare Provider

We’ve only scratched the surface on the potential concerns about taking 20 mg sildenafil oral doses for better sexual intercourse. 

Drug interactions, your blood pressure and how frequently you plan to take your medication are all factors that need to be discussed with your healthcare provider as they consider levels of sildenafil.

And as mentioned above, medication may not help you much if your ED stems from something psychological

Mood disorders like anxiety and depression can cause performance issues, and a psychiatrist or mental health professional will be able to evaluate whether this is the case for you. If so, they may recommend other treatment options. 

Just learning about ED? Take some time to explore these resources to see if sildenafil (Viagra) is right for you. 

This article is for informational purposes only and does not constitute medical advice. The information contained herein is not a substitute for and should never be relied upon for professional medical advice. Always talk to your doctor about the risks and benefits of any treatment or medication.

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