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Sildenafil oral tablet dosage: A detailed guide

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Sildenafil oral tablet is prescribed for erectile dysfunction and pulmonary arterial hypertension in adults. It’s taken by mouth. The frequency of the dose depends on the condition being treated.
Medically reviewed by Rosanna Sutherby, PharmD
Updated on

This article describes sildenafil oral tablet’s dosages, its strengths, and details on how to take it. You’ll also find information on cost savings and coupon options for sildenafil. 

Sildenafil tablet is a generic version of the brand-name drugs Viagra and Revatio. Sildenafil also comes in an injectable form and a liquid suspension that you take by mouth, but those forms aren’t described in this article. To learn more about the injection and liquid suspension, talk with your doctor. 

If you want to know more about sildenafil, see this overview article. It covers details about the drug’s uses, side effects, and more.  

Form and strengths of sildenafil

Sildenafil comes as follows: 

  • Form: a tablet that you swallow 
  • Strengths: 
    • 20 milligrams (mg) 
    • 25 mg 
    • 50 mg 
    • 100 mg 

Dosage of sildenafil 

This article describes the recommended dosages* for sildenafil oral tablet.  

If your doctor prescribes this medication, they’ll determine the dosage that’s best for you. Do not change your dosage of sildenafil oral tablet without your doctor’s recommendation.  

* The drugmaker provides these recommended dosages. If your doctor prescribes sildenafil, be sure to take the dosage they prescribe for you.  

Usual recommended dosages of sildenafil in adults 

Usually, doctors start by prescribing a low dosage of sildenafil oral tablet. Then, they’ll adjust it over time until the right dosage is reached. Ultimately, your doctor will prescribe the smallest dosage of sildenafil that gives the desired outcome. 

The information below describes dosages that are commonly prescribed. That said, always take the dosage your doctor prescribes for you. Your doctor will determine the dosage that best meets your needs. 

Dosage for erectile dysfunction (ED) 

The information below summarizes the recommended dosage for ED

  • Starting sildenafil citrate dosage:* 50 milligrams (mg) one time per day, taken 1 hour before sexual activity (or between 4 hours and 30 minutes before sexual activity) 
  • Maximum dosage: 100 mg one time per day 

* “Sildenafil citrate” is the full drug name of sildenafil. 

Dosage for pulmonary arterial hypertension (PAH) 

The information below summarizes the recommended daily dosage for PAH

  • Dose: 20 mg 
  • Frequency: three times per day 

Dosage adjustments for sildenafil 

Your doctor will prescribe a dosage of sildenafil oral tablet based on several factors, including: 

  • the specific condition being treated and how severe it is 
  • your age 
  • other health conditions you may have 
  • your response to the first dose 
  • other medications you take 

In some people taking sildenafil for ED, doctors might prescribe a starting dosage lower than the recommended dosage. They include older adults (usually considered ages 65 years and older). These also include people who have liver or kidney problems or take certain other medications. 

Missed dose of sildenafil 

If you take sildenafil oral tablets for PAH, talk with your doctor or pharmacist right away if you realize you forgot a dose. They can advise whether you should take the missed dose. Or they can advise whether you should skip it and take your next dose as scheduled. 

For ED, the manufacturer recommends taking sildenafil 1 hour before sexual activity. If this isn’t convenient, you can take the medication between 4 hours and 30 minutes before sexual activity. 

For tips on how to plan your doses of sildenafil and avoid missing a dose, read this article. You could also try: 

  • downloading a reminder app on your phone 
  • setting an alarm 
  • putting a note where you’ll see it, such as on your calendar, bathroom mirror, or bedside table 
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Frequently asked questions 

Below are answers to some commonly asked questions about sildenafil oral tablet and its dosage. 

Are there any reviews on 100-mg or 50-mg sildenafil doses? 

Different doses of sildenafil oral tablets won’t affect everyone the same way. The usual dosage for erectile dysfunction is 50 milligrams (mg) once per day, usually taken 1 hour before sexual activity. Based on how it affects you, your doctor might recommend increasing the dose to 100 mg or decreasing it to 25 mg. 

If you have questions or concerns about the dose of sildenafil tablets, talk with your doctor or pharmacist. 

Is sildenafil used for high blood pressure? If so, what’s the sildenafil dosage for high blood pressure? 

Sildenafil oral tablet treats a specific kind of high blood pressure. It’s called pulmonary arterial hypertension (PAH), which affects the lungs. For this condition, the usual dosage is 20 mg taken 3 times per day. 

Sildenafil isn’t approved to treat any other type of high blood pressure besides PAH. 

When taking sildenafil oral tablets for erectile dysfunction (ED), it can lower your blood pressure. In turn, this can increase the effects of other drugs taken during sildenafil treatment. For example, these include drugs that treat high blood pressure. Additionally, these include medications known to cause low blood pressure as a side effect. 

If you take sildenafil for ED, be sure your doctor knows about all other medications you take. You and your doctor can discuss how taking sildenafil with these other drugs might affect your blood pressure. 

Do doctors prescribe sildenafil dosages by weight? 

No, the dosage of sildenafil oral tablets isn’t based on weight. But your sildenafil dosage may vary based on other factors, such as: 

  • your age 
  • other medications you take 
  • how your body reacts to this medication 

The recommended dosage for erectile dysfunction is 50 mg one time per day, taken 1 hour before sexual activity. But you can take your dose between 4 hours and 30 minutes before sexual activity. For some people, doctors may lower the dose to 25 mg. (This lower dose is discussed in the next question.) For others, doctors may increase the dose to 100 mg. 

The usual dosage for pulmonary arterial hypertension is 20 mg taken three times per day. 

If you have questions about the right dosage for your condition, talk with your doctor or pharmacist. 

Is a sildenafil 20-mg dose used for erectile dysfunction (ED)? 

No, it’s not. Sildenafil oral tablet’s dose of 20 mg is approved to treat pulmonary arterial hypertension

The lowest dosage for ED is 25 mg taken 1 hour before sexual activity. (Or you can take this dose between 4 hours and 30 minutes before sexual activity.) Generally, this is the dosage recommended as the starting dosage for older adults (usually considered ages 65 years and older). It’s also recommended for people who have liver or kidney problems or take certain medications. 

To learn more about sildenafil dosages, talk with your doctor or pharmacist. 

Is sildenafil used long term? 

It depends on the condition. 

Doctors typically prescribe sildenafil oral tablets as a long-term treatment for pulmonary arterial hypertension. If you and your doctor determine they’re safe and effective for your condition, you’ll likely take them long term. 

But for erectile dysfunction, doctors typically prescribe sildenafil oral tablet only as needed. This means you probably won’t take it every day. And you can choose whether to take it long term or short term.  

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How sildenafil is taken

Sildenafil oral tablet is taken by mouth.  

You can take sildenafil with or without food. But if you take this medication after a high fat meal, it may take longer for the drug to start working. A high fat meal can include foods such as a cheeseburger or fried food. 

For erectile dysfunction (ED), you can take the dose one time per day. You take it between 4 hours and 30 minutes before sexual activity. But sildenafil is most commonly taken 1 hour before sexual activity.  

For pulmonary arterial hypertension (PAH), you’ll take a dose three times per day. Your doctor may advise that you take the doses 4 to 6 hours apart. 

If it’s hard for you to swallow tablets, you can split or crush sildenafil tablets. You may also want to view this article. It provides suggestions on how to swallow medications that come in pill form.  

You can talk with your doctor or pharmacist if you have difficulty taking your medication. They can offer recommendations about taking it. 

Sildenafil coupon

Visit this page to access Optum Perks coupons and get price estimates for sildenafil when you use the coupons. These coupons can provide significant savings on your prescription costs.  

Note: Optum Perks coupons cannot be used with any insurance copays or benefits. 

Overdose of sildenafil 

It’s important that you do not take more sildenafil oral tablets than your doctor prescribes. Doing so can lead to serious side effects. 

What to do if you take too much sildenafil 

If you think you’ve taken too much sildenafil, call your doctor or pharmacist right away. Or you could call 800-222-1222 to speak with someone at America’s Poison Centers. You can also use its online resource. If you have severe symptoms, call 911 or a local emergency number immediately. You can also go to the closest emergency room. 

What to ask your doctor

This article describes the usual recommended dosages for sildenafil oral tablet. If your doctor prescribes this medication, they’ll determine the dosage that’s best for you.  

Do not change your dosage of sildenafil oral tablet without your doctor’s recommendation. You should take sildenafil oral tablet exactly as your doctor prescribes.  

Let your doctor know if you have concerns or questions about your treatment plan. 

Here’s a list of some possible questions you may want to ask your doctor: 

  • Can I take a dose of sildenafil oral tablet every day for erectile dysfunction (ED)
  • How long does it take a dose of sildenafil oral tablet to work for ED? 
  • Will my sildenafil dosage for pulmonary arterial hypertension (PAH) change if I have kidney or liver problems? 
  • Am I more likely to have side effects with a higher dosage of sildenafil oral tablet? 

Disclaimer: Optum Perks has made every effort to make certain that all information is factually correct, comprehensive, and up to date. However, this article should not be used as a substitute for the knowledge and expertise of a licensed healthcare professional. You should always consult your doctor or another healthcare professional before taking any medication. The drug information contained herein is subject to change and is not intended to cover all possible uses, directions, precautions, warnings, drug interactions, allergic reactions, or adverse effects. The absence of warnings or other information for a given drug does not indicate that the drug or drug combination is safe, effective, or appropriate for all patients or all specific uses. 

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