Viagra vs Cialis: Which One is Better?

Written by
The Manual Team
Medically approved by
Dr Earim Chaudry
Last updated
4th May 2021

In 30 seconds…

Viagra and Cialis are the two most popular treatments for erectile dysfunction on the planet. And while the science of each is the same, there are some key differences that may make you choose one over the over. Let Viagra vs Cialis commence!

Their effectiveness is comparable, although this always depends on the user. Cialis (Tadalafil) tends to have less common side effects, but again each case is different. However, Cialis is designed to last longer than Viagra – up to 36 hours, rather than just 4-5 hours in Viagra’s case. Cialis is often thought to have less chance of side effects, too.

So, Viagra vs Cialis, which is better? Unfortunately, there’s no straight answer: it’s really a question of what works best for you.

Cialis and Viagra are two of the most popular treatments for erectile dysfunction (ED) in the world – and they have both been proven to improve sexual performance in men of all ages.

Here, we’re going to be looking at the major differences between the two contenders in the battle of Cialis vs Viagra. From their effectiveness to their side effects, from how long you can expect them to last to the time they take to kick in – there are plenty of differences to consider.

Viagra and Cialis work in the same way. The active ingredient in Viagra is called Sildenafil, whilst the one in Cialis is called Tadalafil. Both of these active agents are what are known as PDE5 inhibitors, which tackle the PDE5 enzyme responsible for controlling the muscle tone supplying the penis. They allow blood to flow more easily to your penis, allowing you to have and keep an erection.

Sildenafil and Tadalafil work on exactly the same principle. That’s why the potential side effects of Cialis and Viagra are often similar – and why these drugs are often grouped together.

What’s the Difference Between Viagra and Cialis?

The primary difference between Viagra and Cialis is the length of time each of the drugs stays in your system. For the active agent Sildenafil to kick in, you generally need to take Viagra an hour before sex. At that time, you’re at peak potential – and the effects last generally for about four to six hours. 

Because of this, Sildenafil is great for an evening’s lovemaking. However, you will need to know when you are going to be wanting it. 

On the other hand, the Tadalafil in Cialis stays active in your system for much longer. You’ll feel its full effects quickly (often 30 mins before anticipated need) and it will remain effective for the next 36 hours. Sometimes even longer. 

So, Tadalafil offers a bit more spontaneity than Sildenafil, as you won’t need to plan a specific window for sex. That’s why they call Cialis the “weekend pill” – because your body is ready all weekend.

Cialis (Tadalafil)

The weekend pill

Known as the “weekend pill” because it is effective for up to 36 hours, Tadalafil is the generic, unbranded version of Cialis. Clinically proven to help you get an erection when you need it.


Best for
Weekend use
Effective in
Effective in 8 out of 10 men
Dosage
2.5mg, 10mg, 20mg

Which is more effective, Viagra or Cialis?

Whilst Cialis and Viagra work on different rhythms, their effectiveness in ED treatment is pretty much identical. Studies show that Tadalafil and Sildenafil are both effective in about sixty to eighty percent of men with ED – depending on the dosage.

In one trial, Sildenafil was found to be effective in 82% of men with ED, whilst Tadalafil was effective in 81% of cases. The difference between the two is really much of a muchness. One thing to consider in deciding between Cialis and Viagra, however, is that Viagra is affected by the foods you eat. A high-fat meal taking Viagra will slow down its effects. This is not true of Cialis, meanwhile.

Cialis Side Effects vs Viagra Side Effects

The side effects of Cialis and Viagra are largely similar – due to the similarity between Tadalafil and Sildenafil. These can include headaches, dizziness, flushing, nasal congestion, and a bit of blurred vision. 

In very rare cases, Cialis and Viagra side effects can include “priapism” – a painful long-lasting erection that can persist for hours – as well as temporary negative effects on sight or hearing. If any of these happen, you should consult a doctor immediately.

The main difference between the side effects of Cialis and Viagra is the rate at which these occur. Changes to your vision are more common with Viagra, whilst Cialis more often tends to cause muscle pain. Side effects of Sildenafil and Tadalafil will differ from person to person. However, it is generally thought that Tadalafil produces less of the more common side effects.

Which One is Safer?

Both Tadalafil and Sildenafil are licensed and safe to use. And whilst Tadalafil is thought to be tolerated better by most men, this has not been clinically confirmed. 

All PDE5-inhibitors can be dangerous for men who are on drugs containing nitrates – i.e. drugs for heart disease, e.g. angina, or for high blood pressure or serious cardiovascular disease. It is also not recommended that you take either Sildenafil or Tadalafil with alcohol, because it can cause a drop in blood pressure and may blunt the response of the drugs by impacting blood flow and libido.

If you are intending to take either of these drugs for ED treatment, talk to an online clinician. This is particularly true if you have any heart conditions or health problems.

How do you choose which one is better for you?

The effects of Sildenafil and Tadalafil are not identical in every person that takes them. For some, one can be more effective than the other. For others, one can appear with greater side effects. 

When you are deciding on which ED medication to commit to, it is often advised for you to try both Viagra and Cialis to see which you prefer. 

The other part of your decision of Cialis vs Viagra will be your lifestyle. Do you want a drug that will be effective all weekend? Or one that you can just pop when you need it? Really, the choice is down to you.

Key Takeaways…

So, Cialis vs Viagra – who won? As we say, the choice really is yours, depending on the way in which you want to take your ED treatment. There isn’t one that is “better”; it’s rather a case of which works best for you. Try them out and see – but contact us to talk to a Manual clinician if you’re in any doubt.

Erections aren’t always easy for millions of men in the UK. It’s no big deal. Choose from highly effective, clinically proven solutions.

While we've ensured that everything you read on the Health Centre is medically reviewed and approved, information presented here is not intended to be a substitute for professional medical advice, diagnosis, or treatment. It should never be relied upon for specific medical advice. If you have any questions or concerns, please talk to your doctor.

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