Tadalafil 10mg vs 20mg: Which Dose Is Right?

Tadalafil 10mg vs 20mg: Which Dose Is Right for You?

Published: 17 October 2026

When comparing tadalafil 10mg vs 20mg, both doses work in the same way to help treat erectile dysfunction, but the higher strength may offer a stronger effect for some men. Tadalafil is the active ingredient in Cialis and is known for its long duration of action—up to 36 hours—giving you flexibility and spontaneity [4]. Understanding the differences between these two doses can help you and your prescriber choose the most suitable option for your needs.

How Tadalafil 10mg and 20mg Work

Both tadalafil 10mg and 20mg belong to a class of medicines called PDE5 inhibitors, which work by relaxing blood vessels in the penis to improve blood flow during sexual stimulation [4]. Neither dose will cause an automatic erection—sexual arousal is still needed for the medicine to work. The main difference between the two strengths lies in the amount of active ingredient, which can influence how strong the effect is and how well it works for you.

Tadalafil is taken on-demand, at least 30 minutes before sexual activity, and its effects can last up to 36 hours, earning it the nickname 'the weekend pill' [4]. This extended window means you don't need to time intimacy as precisely as with shorter-acting treatments. Both doses are taken once daily at most, and you should never take more than one tablet in 24 hours.

Tadalafil 10mg vs 20mg: Onset and Duration

The onset time for both tadalafil 10mg and 20mg is similar: you should take either dose at least 30 minutes before sexual activity, though some men find it works within 15–20 minutes [4]. The medicine reaches peak levels in the bloodstream around two hours after taking it, but you may notice an effect earlier. Because tadalafil has a long half-life, the 10mg and 20mg doses both offer the same extended duration—up to 36 hours—allowing for multiple opportunities for intimacy without needing to take another tablet.

The higher 20mg dose does not make tadalafil work faster or last longer than the 10mg dose; instead, it may provide a stronger effect for men who do not respond adequately to the lower strength [4]. Your prescriber will usually start you on 10mg and adjust the dose based on how well it works and whether you experience side effects. If 10mg is effective and well-tolerated, there may be no need to increase to 20mg.

Can You Split a 20mg Tablet?

Some men wonder if they can split a 20mg tadalafil tablet to create two 10mg doses. While tadalafil tablets are not scored (designed to be split), they can technically be divided if your prescriber advises it. However, splitting tablets may not always give you an exact dose, and it is important to follow your prescriber's instructions. If you are prescribed 10mg, it is usually better to take a 10mg tablet rather than splitting a 20mg one, unless your prescriber specifically recommends otherwise for cost or convenience reasons.

Food, Alcohol, and Lifestyle Factors

One of the advantages of tadalafil over some other ED treatments is that food does not significantly affect how it works [4]. You can take both 10mg and 20mg doses with or without meals, including high-fat foods, without worrying about reduced effectiveness. This makes tadalafil a convenient choice if you prefer not to plan around mealtimes.

However, heavy alcohol consumption can worsen erectile dysfunction and increase the risk of side effects such as dizziness, headache, and low blood pressure when combined with tadalafil [4]. Moderate drinking (one or two units) is usually fine, but it is best to avoid excessive alcohol if you want the medicine to work optimally. Grapefruit juice can raise tadalafil levels in the blood and should be avoided, as it may increase the risk of side effects [4].

Lifestyle factors such as smoking, lack of exercise, poor diet, and stress can all contribute to ED [1]. While tadalafil can help manage symptoms, addressing these underlying factors—through regular physical activity, a balanced diet, and stress management—can improve your overall sexual health and may enhance the effectiveness of treatment.

Side Effects: Tadalafil 10mg vs 20mg

The side effects of tadalafil are generally similar for both the 10mg and 20mg doses, but higher doses may slightly increase the likelihood or intensity of certain effects [4]. Common side effects include headache, indigestion, back pain, muscle aches, flushing, and nasal congestion. These are usually mild and temporary, often resolving within a few hours. Back pain and muscle aches are more characteristic of tadalafil than other PDE5 inhibitors and typically appear 12–24 hours after taking the tablet.

Serious side effects are rare but require urgent medical attention. These include an erection lasting more than four hours (priapism), sudden loss of vision or hearing, or chest pain during sexual activity [4]. If you experience any of these, stop taking tadalafil and seek immediate help by calling 999 or going to A&E. Men taking the 20mg dose should be particularly vigilant, as the higher strength may carry a marginally higher risk of side effects, though this varies from person to person.

If you find that 20mg causes bothersome side effects, your prescriber may reduce your dose to 10mg. Conversely, if 10mg is well-tolerated but not quite effective enough, increasing to 20mg may be appropriate. Always discuss any side effects with your prescriber or pharmacist rather than stopping the medicine abruptly.

Managing Common Side Effects

Headaches and indigestion can often be managed with simple measures: staying hydrated, taking a mild painkiller such as paracetamol (not aspirin or ibuprofen if you are on other blood-pressure medicines without checking first), and avoiding heavy or spicy meals. Back pain and muscle aches usually improve on their own, but gentle stretching or a warm bath may help. If side effects persist or become troublesome, speak to your prescriber about adjusting your dose or trying a different ED treatment.

Who Should Take 10mg and Who Might Need 20mg?

The standard starting dose of tadalafil for most men is 10mg, taken on-demand before sexual activity [4]. This dose is effective for many men and is generally well-tolerated. Your prescriber will assess your overall health, other medicines you take, and any underlying conditions before recommending a dose. If you are new to tadalafil, you will usually start with 10mg and use it on at least a few occasions to see how well it works for you.

The 20mg dose is typically reserved for men who have tried 10mg and found it helpful but not quite strong enough, or for those who did not experience adequate improvement at the lower dose [4]. Some men with more severe ED, or those with certain health conditions such as diabetes, may benefit from the higher strength. However, 20mg is not automatically better—it simply provides a higher dose of the active ingredient, which may or may not be necessary depending on your individual response.

Certain men may need to start on a lower dose or avoid higher doses altogether. For example, if you take medicines that interact with tadalafil (such as potent CYP3A4 inhibitors like ritonavir or ketoconazole), your prescriber may limit you to a maximum of 10mg or even lower [4]. Men with moderate liver or kidney impairment may also require dose adjustments. Your prescriber will review your full medical history and current medicines during the online consultation to determine the safest and most effective dose for you.

Getting Tadalafil 10mg or 20mg at Cured Pharmacy

At Cured Pharmacy, both tadalafil 10mg and 20mg are available on prescription following an online consultation with a UK-registered prescriber. You will complete a short health questionnaire covering your medical history, current medicines, and any conditions that might affect your suitability for tadalafil. A prescriber will review your answers, and if tadalafil is appropriate, they will issue a prescription and recommend the most suitable dose—usually starting with 10mg.

We offer several tadalafil options, including generic tadalafil at £7.95 (£6.36 with first-order code Ednew), Tadalafil 20mg (Teva) at £9.99 (£7.99 with code Ednew), Avarante (tadalafil) 10mg at £11.49 (£9.19 with code Ednew), and branded Cialis at £12.00 (£9.60 with code Ednew). All are clinically equivalent and contain the same active ingredient; the choice often comes down to personal preference and budget.

Once your prescription is approved, your order is dispensed by our GPhC-registered pharmacy and delivered discreetly to your door, usually within 1–3 working days. If you have any questions about which dose or product is right for you, our pharmacist-led team is here to help. You can also message our clinical team through your account if you need advice after starting treatment.

Switching Between Doses

If you have been taking 10mg and want to try 20mg (or vice versa), you will need to request a dose change through a follow-up consultation. Do not take two 10mg tablets to make 20mg, as this is not safe and exceeds the maximum daily dose. Similarly, do not split a 20mg tablet without your prescriber's advice. Your prescriber can adjust your prescription based on your experience and any side effects, ensuring you are on the most appropriate dose for your needs.

Scientific References

1. NHS. (n.d.). Erectile dysfunction (impotence). NHS website. https://www.nhs.uk/conditions/erection-problems-erectile-dysfunction/ [accessed 17 October 2026]
2. National Institute for Health and Care Excellence. (n.d.). Erectile dysfunction. Clinical Knowledge Summaries. https://cks.nice.org.uk/topics/erectile-dysfunction/ [accessed 17 October 2026]
3. Joint Formulary Committee. (n.d.). Tadalafil. British National Formulary. NICE. https://bnf.nice.org.uk/drugs/tadalafil/ [accessed 17 October 2026]

Information on this page is for educational purposes only and is not medical advice. Prescription treatments require clinical assessment by a UK-registered prescriber. Always consult a qualified healthcare professional before starting or changing any medication.

Get Treatment in 3 Steps

1

Choose your treatment

Select from our recommended UK-licensed medications.

2

Answer quick questions

Select safe UK treatments. Quick answers.

3

Get it delivered fast

We will deliver direct to you as quickly as tomorrow.