Viagra vs Cialis: Which ED Treatment Works Best?

When comparing ED treatments, understanding how long Viagra works versus Cialis is crucial for making the right choice. Viagra typically works for 4-6 hours, whilst Cialis can last up to 36 hours. Both medications are effective PDE5 inhibitors, but they differ in duration, onset time, and cost. EverydayMeds offers both branded Viagra and generic sildenafil options, allowing patients to choose based on their preferences and budget after completing our clinical assessment.

  • Viagra works for 4-6 hours, Cialis lasts up to 36 hours
  • Both require sexual stimulation to be effective
  • Generic sildenafil offers the same benefits as Viagra at lower cost
  • Food affects Viagra more than Cialis onset times
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 Long Does Viagra Work Compared to Cialis?

Duration of Action: Key Differences

The most significant difference between these medications lies in how long they remain effective. Viagra and its generic equivalent sildenafil typically work for 4-6 hours after taking a dose. This doesn't mean you'll have an erection for this entire period - rather, the medication may help you achieve erections when sexually aroused during this timeframe.

Cialis, containing the active ingredient tadalafil, can remain effective for up to 36 hours. This extended duration has earned it the nickname "the weekend pill" among some users. However, like Viagra, sexual stimulation is still required for the medication to work.

Onset Times and Food Interactions

Viagra usually begins working within 30-60 minutes of taking a dose. However, fatty meals can delay its absorption and effectiveness. For optimal results, many patients prefer taking Viagra on an empty stomach or after a light meal.

Cialis typically takes 30-120 minutes to become effective, but food has less impact on its absorption. This can make meal timing less of a consideration when planning to take Cialis.

Choosing Between Branded and Generic Options

At EverydayMeds, patients can choose between branded Viagra and generic sildenafil during checkout. Both contain the same active ingredient (sildenafil citrate) and work identically in the body. The main difference is cost - generic sildenafil typically offers significant savings whilst providing the same therapeutic benefits.

This choice between branded and generic extends to tadalafil as well, with generic versions of Cialis available at lower prices than the branded medication.

Effectiveness and Success Rates

Clinical studies suggest both medications are highly effective for treating erectile dysfunction. Viagra and sildenafil work for approximately 70-80% of men who try them, whilst Cialis shows similar success rates. The choice often comes down to personal preference regarding duration of action and timing flexibility.

Side Effects and Tolerability

Both medications share similar side effect profiles, including potential headaches, facial flushing, indigestion, and nasal congestion. These effects are usually mild and temporary. However, some men may tolerate one medication better than another.

Due to Cialis's longer duration, some side effects may persist longer than with Viagra. Conversely, the shorter duration of Viagra means any unwanted effects typically resolve more quickly.

Cost Considerations

Generic sildenafil represents excellent value for money, offering the same active ingredient as branded Viagra at a significantly lower cost. For patients who find Viagra effective, choosing the generic option can provide substantial savings over time.

Similarly, generic tadalafil costs less than branded Cialis, making the longer-acting option more accessible to patients seeking extended duration of action.

Dosage Flexibility

Both medications are available in multiple strengths. Viagra and sildenafil come in 25mg, 50mg, and 100mg tablets, whilst Cialis is available in 5mg, 10mg, and 20mg options. Most patients start with a middle dose (50mg for sildenafil, 10mg for tadalafil) which can be adjusted based on effectiveness and tolerability.

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