Tadalafil 20mg 4 Tablets

Tadalafil tablets are a prescription treatment for erectile dysfunction (ED) in adult men. Tadalafil is the same active ingredient as Cialis, supplied here as a generic medicine in 10mg and 20mg tablets for use when needed. It works for up to 36 hours. To get tadalafil from Bury Healthcare Online you complete a short online consultation, and a UK prescriber reviews your answers before anything is dispatched.

How to get tadalafil tablets online

1. Choose your strength and pack size, then select Start Consultation. Your choice is a preference: the final decision is made with your prescriber.
2. Complete a short online consultation about your health, blood pressure and any medicines you take. It takes about 5 to 10 minutes.
3. A UK prescriber reviews your answers before anything is dispatched. They may ask you questions, suggest a different medicine or strength, or decide treatment is not suitable. If it is not suitable, you get a full refund.
4. Approved orders are dispatched from our GPhC-registered pharmacy in Bury (GPhC 1126145).

We supply up to 16 tablets per order. Every order is reviewed by a prescriber.

What is tadalafil?

Tadalafil is the active ingredient in Cialis. Generic tadalafil tablets contain the same medicine at the same strengths and are made to the same UK standards, but cost less. The manufacturer of the generic tablets we supply may vary. For a daily low-dose option see tadalafil once a day; for the branded version see Cialis.

How tadalafil works

Tadalafil is a PDE5 inhibitor. During sexual arousal it helps the blood vessels in the penis relax, so more blood can flow in and an erection is easier to get and keep. You still need to be sexually stimulated: it does not cause an erection on its own, does not increase sex drive and is not a cure.

Who should not take tadalafil

Tadalafil is for adult men aged 18 or over with erectile dysfunction. Do not take it if:

• You are allergic to tadalafil or any of the other ingredients.
• You take any nitrate medicine for chest pain (for example GTN spray or tablets, isosorbide mononitrate or isosorbide dinitrate), or use “poppers” (amyl nitrite or other nitrites).
• You take riociguat for pulmonary hypertension.
• You have had a heart attack in the last 90 days or a stroke in the last 6 months.
• You have unstable angina or angina during sex, heart failure in the last 6 months, an uncontrolled irregular heartbeat, low blood pressure, or uncontrolled high blood pressure.
• Your doctor has advised you not to have sex because of a heart problem.
• You have ever lost sight in an eye because of reduced blood flow to the optic nerve (NAION).

Tell your prescriber about:

• Heart problems, high or low blood pressure, or an irregular heartbeat
• Liver or kidney problems
• A bleeding disorder or an active stomach ulcer
• A condition that affects the shape of the penis (such as Peyronie’s disease), or a condition that makes a long-lasting erection more likely (such as sickle cell anaemia, multiple myeloma or leukaemia)
• Other medicines, especially alpha-blockers (for example doxazosin or tamsulosin), other blood pressure medicines, HIV medicines (such as ritonavir), certain antifungals (ketoconazole, itraconazole) and certain antibiotics (clarithromycin, erythromycin)
• Any other treatment for erectile dysfunction

The consultation asks about all of these. Some answers mean we cannot supply online and will direct you to your GP.

How to take tadalafil

• Take one tablet with water at least 30 minutes before sex. It can take up to 2 hours to reach its full effect.
• It keeps working for up to 36 hours, so you do not need to plan sex around the tablet.
• Food does not affect how well it works.
• Do not take more than one tablet a day. On-demand 10mg and 20mg tablets are not meant to be taken every day; if you expect to have sex twice a week or more, ask about the once-a-day 5mg tablet.
• Avoid drinking a lot of alcohol, which can lower blood pressure and make erections harder.

Your prescriber decides the right strength from your consultation answers.

Side effects

Like all medicines, tadalafil can cause side effects, although not everybody gets them. They are usually mild and become more likely at higher doses.

• Common (up to 1 in 10 men): headache, indigestion, back pain, muscle aches, aching arms and legs, flushing, blocked nose

Back pain and muscle aches usually come on 12 to 24 hours after a dose and settle within 48 hours. See the safety section below for the rare but serious effects that need urgent help.

Sildenafil, tadalafil and vardenafil compared

All three are PDE5 inhibitors and work in the same way. The main differences are how soon they start working, how long the window lasts and whether food makes a difference. Your prescriber can help you choose.

Important safety information

Get medical help straight away (call 999 or go to A&E) if you have:

• An erection that lasts more than 4 hours
• Chest pain during or after sex. Tell the medical team you have taken an erectile dysfunction medicine, because nitrates must not be given to you.
• Sudden loss of vision or sudden loss or decrease in hearing. Stop taking the medicine.
• A severe allergic reaction, such as swelling of the face, lips or throat, or a severe skin reaction

This page is a summary. Always read the patient information leaflet supplied with your medicine. Erectile dysfunction can be an early sign of heart disease, diabetes or high blood pressure, so it is worth seeing your GP for a health check as well. You can report side effects through the MHRA Yellow Card scheme.

Medically reviewed by Hassan Khan, MPharm, Independent Prescriber — Superintendent Pharmacist, Bury Healthcare Online (GPhC-registered pharmacy 1126145). Last reviewed: October 2026. Information checked against the UK Summary of Product Characteristics.

Frequently asked questions