Essential Viagra Quick Facts Guide

Get instant access to essential Viagra quick facts with our comprehensive reference guide. Whether you're considering treatment for erectile dysfunction or need specific information about dosage, timing, or side effects, this guide provides the key facts you need to know. EverydayMeds offers both branded Viagra and generic sildenafil options, allowing you to choose the treatment that best suits your needs. All our treatments require a clinical consultation with a UK-licensed prescriber to ensure safe and appropriate use.

  • Works within 30-60 minutes and effects can last up to 6 hours
  • Available in 25mg, 50mg, and 100mg tablets with 50mg as the standard starting dose
  • Requires sexual arousal to work - does not cause automatic erections
  • Maximum one dose per 24 hours with prescription-only status in the UK
Start your free consultation

Takes less than 2 minutes to complete, 100% online

More pleasure. Less waiting. Built to last.

Get Started

Not sure which one? Here's the honest comparison.

Sildenafil
~60 min
~4 hrs
you like to plan ahead
Tadalafil (as-needed)Most prescribed
~30 min
up to 36 hrs
you want a whole weekend covered
Tadalafil Daily
always active
continuous
you never want to think about timing
Vardenafil
~15–30 min
~8 hrs
you want the fastest onset

How ED treatment works in your body.

Increases blood flow

Increases blood flow

When PDE5 is suppressed, blood is able to flow more freely through the body—including to the (you guessed it) penis.

Increase erections

Increase erections

More blood flow to the penis means harder, more satisfying erections once you're sexually stimulated.

Complete Viagra Reference Information

How Viagra Works

Viagra contains sildenafil citrate, which belongs to a group of medicines called PDE5 inhibitors. The medication works by blocking the phosphodiesterase type 5 enzyme, which increases blood flow to the penis during sexual arousal. Importantly, Viagra does not cause automatic erections - sexual stimulation is still required for the medication to be effective. The treatment is designed to help men achieve and maintain erections suitable for sexual activity.

Dosage and Timing Quick Facts

Viagra is available in three tablet strengths: 25mg, 50mg, and 100mg. Most men start with the 50mg dose, which can be adjusted up to 100mg or down to 25mg based on effectiveness and tolerability. Take one tablet approximately 30-60 minutes before sexual activity. The effects typically begin within 30-60 minutes and can last for up to 6 hours, though this doesn't mean the erection lasts for this duration.

Never exceed one dose within a 24-hour period. For optimal results, avoid taking Viagra immediately after a large or high-fat meal, as this can delay how quickly the medication works. Taking the tablet on an empty stomach or after a light meal typically provides faster results.

Common Side Effects to Expect

Understanding potential side effects helps you know what to expect when taking Viagra. Headache is the most common side effect, experienced by more than 1 in 10 men. Other frequent side effects include facial flushing, indigestion, nasal congestion, dizziness, visual disturbances (such as a blue tinge to vision), and nausea. Most side effects are mild and temporary, often reducing with continued use as your body adjusts to the medication.

Important Safety Information

Viagra must never be taken with nitrate medications, including GTN spray, isosorbide tablets, or recreational substances known as "poppers" containing amyl nitrite. This combination can cause a dangerous drop in blood pressure. Similarly, men taking riociguat for pulmonary hypertension cannot use Viagra safely.

Seek immediate medical attention if you experience an erection lasting more than 4 hours (priapism), sudden vision or hearing loss, chest pain during sexual activity, or signs of a severe allergic reaction. These situations require urgent medical assessment.

Who Can Take Viagra

Viagra is suitable for adult men over 18 with erectile dysfunction who have completed a clinical assessment. The medication requires a prescription following consultation with a UK-licensed prescriber who will evaluate your cardiovascular health, current medications, and medical history. Men with severe heart disease, recent heart attacks or strokes, severe liver problems, or very low blood pressure may not be suitable candidates for treatment.

Branded vs Generic Options

EverydayMeds offers both branded Viagra and generic sildenafil, giving you choice in your treatment. Both contain the same active ingredient (sildenafil citrate) and have identical effectiveness and safety profiles. Viagra is the original branded version manufactured by Pfizer, whilst sildenafil is the generic alternative that typically costs less. The choice between branded and generic is a matter of personal preference - both are clinically equivalent.

Alcohol and Food Interactions

Moderate alcohol consumption is unlikely to cause problems when taking Viagra, but excessive drinking can reduce the medication's effectiveness and worsen side effects like dizziness. Both alcohol and sildenafil can lower blood pressure, so limiting alcohol intake is advisable. Avoid grapefruit and grapefruit juice, as these can increase sildenafil levels in your blood and potentially intensify side effects.

What you need to know about erectile dysfunction

It's one of the most common conditions we treat, and one of the most treatable.

What is Erectile Dysfunction?
ED means finding it hard to get or keep an erection firm enough for sex. It's not unusual to have an off night; the point at which it's worth doing something is when it's happening regularly, or when it's starting to bother you.
How will I feel when I take ED medication?
For most men, nothing feels different day to day. The medication works in the background — when you're sexually aroused, it helps blood flow where it's needed, so erections come more easily and last longer. It doesn't cause arousal on its own. Some men notice mild, short-lived effects like a headache, facial flushing or a stuffy nose, which usually pass as the dose wears off.
Why do I need a prescription for ED medication?
ED treatments are prescription-only medicines in the UK because they aren't suitable for everyone — for example, alongside certain heart conditions or medications like nitrates. That's why we ask you to complete a short online consultation first. A UK-registered prescriber reviews your answers to make sure your chosen treatment is safe and right for you before it's dispensed.
Couple laughing together

How it works

Achieve your goals in just a few simple steps.

Step 1

Start Free Consultation

Select safe UK treatments. Quick answers.

Step 2

Review By Our Clinical Team

Our expert team will use your consultation as the basis of our recommendation and communicate with you.

Step 3

Get it delivered fast

We’ll deliver direct to you, as quickly as tomorrow.

Frequently asked questions