The Difference between Sildenafil and Tadalafil

Erectile Dysfunction (ED) is one of the most common sexual dysfunctions.

It is defined as the difficulty in getting or maintaining an erection sufficient to allow for satisfactory sexual intercourse.

The Science

Normally when you are aroused your tissues release a chemical called nitric oxide which in turn causes the release of a chemical called cyclic guanosine monophosphate (cGMP). It is cGMP that causes the muscles at the sides of your penis to relax and allows the blood to rush in.

However, for some, an enzyme called phosphodiesterase-5 (PDE5) breaks down cGMP. The consequence is this either prevents you from getting an erection or makes it easier to lose an erection.

Both Sildenafil and Tadalafil are referred to as PDE5 inhibitors meaning they block the action of PDE5. This allows the levels of cGMP to remain high so that the muscles at the side of your penis are relaxed, more blood rushes in, and you can achieve a firmer and longer lasting erection.

Both Sildenafil and Tadalafil work in the presence of a chemical which is released when sexually stimulated. A chain reaction begins once this natural chemical is released. This means you must be sexually aroused for Sildenafil or Tadalafil to be most effective.

What is Sildenafil?

Sildenafil is the generic or unbranded form of Viagra. Sildenafil is a treatment that is clinically proven to be highly effective in helping you get and keep an erection. It is the most widely taken treatment for ED globally. Sildenafil starts working within an hour after being ingested and stays in the system for 4 hours.

What is Tadalafil?

Tadalafil is the generic or unbranded form of Cialis. Tadalafil is clinically proven to be highly effective in tackling ED in a similar way to Sildenafil. Tadalafil has a faster start time (starts working within 30 minutes) and duration of action (it remains in your system for 36 hours). It’s commonly known as the “weekend pill” for its long-lasting effects.

How do you choose?

There is no significant difference between the two although we find that men seem to prefer Tadalafil on the basis of its faster starting time and longer lasting effects. Tadalafil is also more effective when taken with food.

Which you should choose ultimately depends on which is the best fit for your personal needs and lifestyle. The longer-acting Tadalafil may be the best choice if you don’t want to have to coordinate having sexual activity, or when it is less concentrated, say on a weekend. If you are having sex more spontaneously then Sildenafil may be the best option for you.

At Man Behind The Mirror, we offer both Sildenafil and Tadalafil, with discreet delivery within 2-3 working days. 

You may purchase your ED treatment here.

If you have any follow-up questions don't hesitate to contact us at

Written by Mike Firth, GP and Medical Director

This article is for informational purposes only and is not a substitute for professional medical advice or diagnosis. Always talk to your doctor about the risks and benefits of any treatment.