What Will Viagra Do? Complete Effects Guide

Viagra is Pfizer's brand name for sildenafil citrate, a prescription medication designed to help men with erectile dysfunction achieve and maintain erections suitable for sexual activity. Understanding what Viagra does, how it works, and what to expect can help you make informed decisions about ED treatment. EverydayMeds offers both branded Viagra and generic sildenafil options following a clinical assessment by UK-licensed prescribers.

  • Increases blood flow to the penis when sexually aroused
  • Takes effect within 30-60 minutes of taking
  • Effects can last 4-6 hours but requires sexual stimulation
  • Available in 25mg, 50mg, and 100mg strengths
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.

How Viagra Works and What to Expect

How Viagra Works in Your Body

Viagra contains sildenafil citrate, which belongs to a class of medications called PDE5 inhibitors. When you become sexually aroused, your body naturally releases nitric oxide, which increases blood flow to the penis. Viagra works by blocking the PDE5 enzyme that can reduce this blood flow, helping you achieve and maintain an erection suitable for sexual activity.

What Effects You Can Expect

Viagra typically begins working within 30-60 minutes of taking it on an empty stomach. The medication can remain effective for up to 4-6 hours, though this doesn't mean you'll have an erection for this entire time. Sexual stimulation is still required for the medication to work effectively. Many men find the 50mg starting dose effective, though your prescriber may recommend adjusting to 25mg or 100mg based on your response and any side effects experienced.

Branded Viagra vs Generic Sildenafil

EverydayMeds offers both Pfizer's branded Viagra and generic sildenafil options. Both contain the same active ingredient (sildenafil citrate) and work identically in your body. The main difference is cost, with generic sildenafil typically being more affordable whilst providing the same therapeutic effects. You can choose between branded or generic options during checkout after completing your clinical assessment.

Common Side Effects and What to Expect

Most men tolerate Viagra well, though some may experience mild side effects such as headache, facial flushing, indigestion, or nasal congestion. These effects are usually temporary and tend to decrease as your body adjusts to the medication. Rarely, some men may experience changes in vision or prolonged erections lasting more than 4 hours, which require immediate medical attention.

Getting Started with Viagra

Before starting Viagra, you'll need to complete a clinical assessment with one of our UK-licensed prescribers. This evaluation ensures the medication is safe and suitable for your individual health profile, considering factors like cardiovascular health, current medications, and medical history. The assessment can be completed discreetly online, with your medication delivered in plain packaging if approved.

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