If you’re looking for treatment for erectile dysfunction (ED), you’ve probably seen both tadalafil and Cialis. So what’s the difference? The answer is simple, they contain the same active ingredient.
Tadalafil is the name of the medicine, Cialis is the brand name used by Eli Lilly. After the patent expired, other manufacturers started making tadalafil and selling it under its generic name. That’s why you’ll often see tadalafil referred to as Cialis. The medicine is the same, but the brand, manufacturer, tablet appearance and price can differ.
Here’s what you need to know about tadalafil vs Cialis, including why one can cost more than the other.
What is the difference between tadalafil and Cialis?
Cialis was launched in the UK by Eli Lilly in 2003. Their patent meant no other company could make a tadalafil tablet in the UK until it expired on 14 November 2017. Generic versions became available after this patent expired, and several manufacturers now make generic tadalafil.
Generic tadalafil tablets might not look like the ones you've seen before, but inside is the same active ingredient at the same strength. The same thing happened with Viagra, which came off patent in 2013 and is now usually dispensed as sildenafil.
Is tadalafil as effective as Cialis?
Yes, there is no evidence that one is more effective than the other. A generic medicine can only be sold in the UK once it has a licence from the Medicines and Healthcare products Regulatory Agency (MHRA), and it must meet the same standards of quality, safety and effectiveness as the original.
Manufacturers now don't need to repeat all the original clinical trials, which is why it’s often cheaper. However they must show the medicine is absorbed and works in the body in the same way as the original. Generic tadalafil can also be cheaper because manufacturers don't have to invest as heavily in branding and marketing. A lower price doesn't mean the medicine is weaker or less effective. The NHS commonly prescribes medicines by their generic name rather than a brand name.
Do tadalafil and Cialis work in the same way?
Tadalafil and Cialis work in the same way as they contain the same active ingredient. Tadalafil is a PDE-5 inhibitor, which means it blocks an enzyme called phosphodiesterase type 5 (PDE-5). This helps the blood vessels in the penis relax, increasing blood flow and making it easier to achieve and maintain an erection when sexually aroused.
Sexual stimulation is still needed for tadalafil to work, so it won't cause an erection on its own. Our guide on what tadalafil is and how it works covers this in more detail.
Are tadalafil and Cialis doses the same?
Yes. Both come in 2.5mg, 5mg, 10mg and 20mg tablets and can be taken in two ways:
Daily: a lower dose (2.5mg or 5mg) taken once a day at around the same time
On demand: a higher dose (10mg or 20mg) taken before sex, no more than once in 24 hour
Our tadalafil dosage guide covers which option might suit you and how to take each one.
There is one small difference worth noting. Cialis Together, a 10mg tadalafil tablet, was reclassified by the MHRA in 2023 and can now be bought over the counter from a pharmacy without a prescription. This is however limited to a maximum of 8 tablets. All other tadalafil products, branded or generic, remain prescription-only.
Do tadalafil and Cialis have the same side effects?
Since tadalafil and Cialis contain the same active ingredient at the same strength, the expected side effects are the same.
The most common side effects are headaches, facial flushing, indigestion, a blocked nose, and back or muscle aches. Our tadalafil side effects guide explains how long they usually last and when something needs checking.
Is generic tadalafil as safe as Cialis?
Yes, as long as you buy it from a regulated source.
Every licensed medicine sold in the UK (generic or branded) must be made to Good Manufacturing Practice (GMP) standards. Licensed generic tadalafil is held to the same standard as Cialis.
It’s important to buy ED medication from a regulated pharmacy. In the UK, legitimate online pharmacies are registered with the General Pharmaceutical Council (GPhC) such as Quick Meds, and you can check a pharmacy's registration on the GPhC register before ordering. Learn more about buying tadalafil online in the UK here.
Why is tadalafil usually cheaper than Cialis?
Bringing a new medicine to market takes years of development and clinical trials, and the patent period is how the original manufacturer recovers that spend.
Once a patent ends, other companies can make the same medicine without repeating the original research. Price differences also come from branding and development costs, rather than the medicine itself. This means paying more for Cialis doesn’t mean you’re getting a stronger or better product.
Should I choose tadalafil or Cialis?
Both contain the same active ingredient, so for most men the decision comes down to preference and practicality:
Generic tadalafil is usually the more affordable option and is available on prescription in all four strengths
Branded Cialis costs more, but some men prefer to stay with the brand they know or the tablet they've used before
Cialis Together is worth considering if you'd rather buy from a pharmacy without a prescription, though it only comes in the 10mg strength with a maximum of 8 tablets in a pack.
If you are unsure which one is appropriate for you you can speak to a clinical pharmacist at Quick Meds.
Speak to Quick Meds about ED treatment
Still not sure which option is best for you? Start your online ED consultation and our prescribing team will review your medical history, current medicines and preferences before recommending a treatment and dose.
