How To Take Sildenafil for Erectile Dysfunction

How To Take Sildenafil

If your healthcare provider just prescribed sildenafil citrate (generic Viagra^®) to treat your erectile dysfunction (ED) symptoms, you’re probably excited to get your mojo back. But it’s also understandable if your head is swimming with questions.

Like other PDE5 inhibitors, or phosphodiesterase type 5 inhibitors, sildenafil is a safe treatment for ED, if used as directed. It’s been Food and Drug Administration (FDA)-approved for this use since 1998, after all.

In an effort to provide some answers to your lingering questions, this guide will explain how to take sildenafil for the best results, a typical starting dosage, and potential side effects to consider. But remember that you should always follow your provider’s instructions for taking sildenafil—or any medication, for that matter.

What Is Sildenafil?

Sildenafil belongs to a class of drugs known as PDE5 inhibitors. These medications block the PDE5 enzyme, resulting in the widening of your blood vessels to promote blood flow to the penis. This increased blood flow results in an erection.

However, sildenafil doesn’t affect your libido. You still need to be aroused to get and maintain an erection long enough to yield satisfying sex.

Typical Sildenafil Dosage

Healthcare providers can prescribe sildenafil tablets in different doses. The most common are:

• 25 milligrams

• 50 milligrams

• 100 milligrams

A typical starting dose of sildenafil is 50 milligrams, which you’d take 30 minutes to four hours before sexual activity. Your provider may adjust your dosage depending on your needs and how you respond to the medication.

It’s also possible you may get a prescription in doses that are multiples of 20 milligrams, including 20 milligrams, 40 milligrams, 60 milligrams, and 80 milligrams. In these cases, your sildenafil tablets would actually be the generic form of Revatio^®, a medication that has the ingredient sildenafil, like Viagra, but is FDA-approved for pulmonary arterial hypertension (although it can be prescribed off-label for ED).

Be sure to talk through all options with your healthcare provider. And, as is the case with taking any medication, following a professional’s medical advice is crucial.

When To Take Sildenafil

Unlike some other ED meds, you don’t take sildenafil every day. Sildenafil is an as-needed medication that should be taken at least about 30 minutes to an hour before sexual activity, and its effects should last up to four hours. You should never take more than one dose per day.

You may be prescribed sildenafil or Viagra if you struggle with the following symptoms:

• Having trouble getting an erection

• Having trouble maintaining an erection

• Getting erections that aren't as firm as you'd like them to be

What Foods To Avoid Before Taking Sildenafil

Some medications can upset your stomach if you don’t take them with food. That’s not the case with sildenafil. You can take this ED medication with or without food.

However, high-fat meals can impact the absorption of sildenafil, leading to lower peak plasma levels of the medication, which can translate to lower efficacy.

Grapefruit juice can also interfere with how the body processes sildenafil, leading to more side effects. So, if you’re a half-grapefruit in the a.m. kind of guy, mention that to your healthcare provider before filling a sildenafil prescription.

How To Store Sildenafil

Keep sildenafil out of the reach of children and pets, and store the medication at room temperature between 68°F to 77°F (20°C to 25°C).

What To Do if Sildenafil Doesn’t Work

You should always follow your doctor’s instructions regarding sildenafil dosing, but your total daily dosage should never exceed 100 milligrams. Even if you’re not getting results from a 100-milligram dose of sildenafil, don’t try to take more.

If sildenafil isn’t helping with your lackluster erections, there are a few possible reasons. You might benefit from:

• A different dose

• A different ED medication

• Another kind of treatment altogether (like therapy for psychological ED)

• Addressing underlying health conditions that can contribute to ED

Additionally, taking sildenafil too early (we’re talking more than a few hours before having sex) won’t produce the effects you’re looking for. 

That means you have to do a bit of sex planning when taking sildenafil. But you might be surprised at how sexy the anticipation can be—for you and your partner. Spend that time exploring new foreplay ideas or sharing your sexual fantasies.

Can I Take Expired Sildenafil?

Avoid taking sildenafil if it’s expired. According to the FDA, you should skip taking any expired meds and safely dispose of them for the following reasons:

• They might be less effective.

• They might be harboring bacteria.

• Their chemical composition could be altered, making them unsafe to consume.

How can you tell if your medications are expired? Check the label for a date, likely next to the abbreviation “Exp.”

Want more tips on how to get the most out of sildenafil? Read our guide on how to use Viagra for best results.

What To Do if You Forget To Take Sildenafil

Good news! It doesn’t really matter if you forget to take sildenafil because it’s designed for you to take it as you need it.

But be careful about accidentally doubling up on doses. Missing a dose before sex is no big deal, though doing so may impact the quality of your erection. However, forgetting you already took sildenafil and taking a subsequent dose within 24 hours can lead to complications, particularly if you go over 100 milligrams total.

More on that below.

Sildenafil Side Effects

You should be aware of the potential side effects when taking any new drug. 

The most common side effects of sildenafil include:

• Headaches 

• Flushing

• Stomach upset

• Nasal congestion

• Muscle and back pain

• Nausea 

• Rash

• Dizziness

Most of these mild side effects will go away on their own as your body adapts to taking sildenafil.

But sildenafil also comes with some more rare but potentially serious side effects like:

• Sudden loss of vision (potentially a sign of non-arteritic anterior ischemic optic neuropathy or NAION)

• Hearing loss

• Allergic reaction 

• Priapism (a painful erection lasting longer than four hours)

If you experience any of these symptoms after taking sildenafil, seek immediate medical attention.

And FYI: Even mild side effects can impact your life. If you get an upset stomach every time you take sildenafil, talk with a healthcare professional. They may recommend changing your dose or switching medications altogether. 

Read more about potential sildenafil reactions in our sildenafil side effects guide.

Sildenafil Interactions

Sildenafil isn’t right for everyone. It might be dangerous to use sildenafil if you have certain medical conditions or take specific drugs.

Here’s what to consider:

• Heart problems. If your healthcare provider told you not to engage in sexual activity because of a heart condition (like a history of heart attack; heart disease; heart failure; angina; or arrhythmia, also known as an irregular heartbeat), it’s probably best to abstain from having sex and taking sildenafil.

• Taking medications for high blood pressure. Using sildenafil when you take medicines for high blood pressure or pulmonary arterial hypertension could cause a dangerous, potentially life-threatening dip in blood pressure. Avoid taking sildenafil with nitrates (medications for chest pain) such as isosorbide dinitrate, isosorbide mononitrate, nitroglycerin, and alpha-blockers or other blood pressure medications like riociguat.

• Priapism risk. If you have a condition that puts you at higher risk of priapism—like sickle cell anemia, leukemia, Peyronie’s disease, or multiple myeloma—you should avoid sildenafil.

• Retinitis pigmentosa. There isn’t enough data to say whether sildenafil is safe for people with this eye condition.

• Recreational drug use. Sildenafil can interact with the nitrites found in certain recreational drugs popularly known as “poppers,” causing a dangerous drop in blood pressure.

• Other PDE5 inhibitors. Don’t mix sildenafil with other ED drugs, like Cialis^®, Levitra^®, Revatio^® (another brand name for sildenafil) or Stendra^®. This can put you at risk for low blood pressure. More of something isn’t always better! 

• Other drugs. Aside from heart medications and other PDE5 inhibitors, taking sildenafil with ritonavir, ketoconazole, itraconazole, or clarithromycin (an antibiotic) can increase the concentration of sildenafil in your body and make you more likely to experience side effects.

• Supplements. Talk with a healthcare professional before mixing sildenafil with over-the-counter supplements, which aren’t regulated in the same way as prescription drugs.

Learn more about health and drug interactions in our sildenafil interactions guide.

Next Steps on How To Take Sildenafil

If you’re living with ED symptoms, you’re not alone. ED affects millions of men worldwide. 

Sildenafil can make it easier to get and keep an erection so you can enjoy a fulfilling sex life.

Here’s what to remember when taking sildenafil for ED:

• Take it at least 30 to 60 minutes and no more than four hours before sexual stimulation. Also, avoid high-fat foods or meals that can slow absorption.

• Don’t mix sildenafil with medications that can cause dangerous interactions. Unsure whether your meds are safe to combine with sildenafil? Ask a healthcare professional. 

• Combine sildenafil with healthy habits. Regular exercise, a balanced diet, and quality sleep can maximize your overall health and sexual well-being.

• Consider alternative treatments if sildenafil doesn’t work for you. Other oral erectile dysfunction medications include tadalafil (generic for Cialis), avanafil (Stendra), vardenafil, and chewable Hard Mints. Your healthcare provider might also recommend adjusting your sildenafil dosage.

Ready to find an erectile dysfunction treatment that works for you? Get advice from one of our healthcare providers to learn more about your options.