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  1. About tadalafil
  2. Key facts
  3. Who can and cannot take tadalafil
  4. Where to get tadalafil
  5. How and when to take it
  6. Side effects
  7. Pregnancy and breastfeeding
  8. Caution with other medicines
  9. Common questions

1. About tadalafil

Tadalafil is a medicine used to treat erection problems (erectile dysfunction) and symptoms of an enlarged prostate (benign prostate enlargement).

It's also sometimes used to treat pulmonary hypertension (high blood pressure in the blood vessels that supply the lungs).

Tadalafil is available on prescription only.

It comes as tablets that you swallow with water. It can be taken with or without food.

2. Key facts

  • It usually takes 30 to 60 minutes for tadalafil to work for erectile dysfunction. You can take it once a day, at least 30 minutes before you want to have sex.
  • Taking tadalafil on its own is not enough to cause an erection. You need to be sexually aroused for it to work.
  • Many men do not have any side effects from tadalafil, while some have mild side effects. These may include headaches, back pain, muscle aches, pain in your arms and legs, facial flushes, stuffy nose, and indigestion.
  • Do not take tadalafil if you also take medicines called nitrates (often prescribed for chest pain). This combination can cause dangerously low blood pressure.
  • Tadalafil is sometimes called the brand names Cialis (for erectile dysfunction and benign prostatic enlargement) or Adcirca (for pulmonary hypertension).

3. Who can and cannot take tadalafil

Tadalafil can only be taken by adults aged 18 and over.

Tadalafil is not suitable for some people.

Do not take tadalafil if you:

  • have had an allergic reaction to tadalafil or any other medicines in the past
  • are taking medicines called nitrates for chest pain
  • have a serious heart and liver problem
  • have recently had a stroke or a heart attack
  • have low blood pressure or uncontrolled high blood pressure
  • have ever lost your vision due to reduced blood flow to the eye

Check with your doctor before taking tadalafil if you:

  • have sickle cell anaemia (an abnormality of red blood cells), leukaemia (cancer of blood cells) or multiple myeloma (cancer of bone marrow)
  • have Peyronie's disease (curved penis) or a similar problem with your penis
  • have liver or kidneys problems
  • have a heart problem – your doctor will advise you whether your heart can take the additional strain of having sex

4. Where to get tadalafil

Tadalafil is only available with a prescription.

On the NHS

Tadalafil is only available for erectile dysfunction if you have a specific condition such as multiple sclerosis or a spinal cord injury.

Tadalafil is not available on the NHS to treat benign prostate enlargement.

Private prescription

If you do not meet the NHS criteria for tadalafil you can get a private prescription from a doctor. This means you'll need to pay the full cost of the medicine.

5. How and when to take it

It's important to take this medicine as advised by a doctor or pharmacist.

Tadalafil tablets come in different strengths.

Swallow your tablets whole, with a drink of water. The tablets can be taken with or without food.

How much will I take for erectile dysfunction?

You usually take tadalafil before having sex. Take 1 tablet at least 30 minutes before you want to have sex. Do not take more than 1 tablet a day.

The usual dose is 10mg. Your doctor may increase or decrease your dose, depending on how well it works and how often you take it.

The effects may last longer than 24 hours, so you're not recommended to take the 10mg or 20mg tablets every day.

For the tablet to work properly, you’ll need to be sexually excited.

If you have a private prescription for tadalafil, read the information that comes with your medicine carefully. The strength and dosage instructions can vary.

How much will I take for benign prostate enlargement?

Tadalafil tablets for an enlarged prostate come as 2.5mg or 5mg. The usual dose is 5mg, taken once a day.

You can take your tablet in the morning or evening, but it’s best to take it at the same time each day.

Your doctor might give you a low dose of 2.5mg if you are having any problems, such as side effects.

If you are being treated for both benign prostatic enlargement and erectile dysfunction, the dose is 5mg.

How much will I take for pulmonary hypertension?

Tadalafil tablets for pulmonary hypertension come in 20mg strength.

The usual dose is 40mg – two 20mg tablets, taken once a day. These tablets are large, so take the tablets one after the other.

If you have kidney or liver problems your doctor might decrease the starting dose to 10mg or 20mg.

What if I forget to take it?

If you have:

  • benign prostatic enlargement – take it as soon as you remember and then continue as usual
  • pulmonary hypertension – take it within 8 hours if you can. If you remember after 8 hours, skip the missed dose and take the next dose as usual.

Never take 2 doses at the same time. Never take an extra dose to make up for a forgotten one.

If you often forget doses, it may help to set an alarm to remind you.

You could also ask a pharmacist for advice on other ways to help you remember to take your medicine.

What if I take too much?

Taking too much tadalafil by accident can cause unpleasant side effects, including:

  • headache
  • dizziness
  • indigestion
  • stuffy nose
  • problems with your vision (such as blurred vision)

Side effects will usually go away when you stop taking the tablets. Talk to a doctor if you have taken too much tadalafil and you're worried about these side effects.

6. Side effects

Like all medicines, tadalafil can cause side effects in some people. Many people have no side effects or only minor ones.

Common side effects

Common side effects happen in more than 1 in 100 people. The side effects may increase with an increasing dose.

If you get these side effects, keep taking the medicine, but tell a doctor or pharmacist if they bother you or do not go away:

  • headaches
  • feeling sick (nausea)
  • red or flushed face
  • indigestion
  • stuffy nose
  • muscle aches

Serious side effects

Serious side effects are rare and happen in less than 1 in 1,000 people.

Stop taking tadalafil and call a doctor straight away if you get:

  • chest pains – if this happens during or after sex, get into a semi-sitting position and try to relax (remember do not use nitrates for chest pain while taking tadalafil)
  • prolonged and sometimes painful erections – if you have an erection that lasts for more than 4 hours, contact a doctor immediately
  • a sudden problem with your eyesight or hearing
  • a serious skin reaction – symptoms may include red raised patches on your skin or red spots (hives), a swollen face and swelling around the eyes
  • seizures or fits

Serious allergic reaction

In rare cases, tadalafil can cause a serious allergic reaction (anaphylaxis).

Immediate action required: Call 999 or go to A&E now if:
  • you get a skin rash that may include itchy, red, swollen, blistered or peeling skin
  • you're wheezing
  • you get tightness in the chest or throat
  • you have trouble breathing or talking
  • your mouth, face, lips, tongue or throat start swelling

You could be having a serious allergic reaction and may need immediate treatment in hospital.

These are not all the side effects of tadalafil. For a full list, see the leaflet inside your medicine packet.


You can report any suspected side effect using the Yellow Card safety scheme.

Visit Yellow Card for further information.

7. Pregnancy and breastfeeding

Women with pulmonary hypertension may be treated with tadalfil.

If you have pulmonary hypertension, tadalafil is not recommended in pregnancy or while breastfeeding.

Non-urgent advice: Tell your doctor if you're:

  • trying to get pregnant
  • pregnant
  • breastfeeding

8. Caution with other medicines

Some medicines do not mix well with tadalafil.

Tell a doctor if you're taking these medicines before you start tadalafil:

  • nitrates for chest pain
  • riociguat for pulmonary hypertension

Mixing tadalafil with herbal remedies and supplements

Some complementary therapies may have ingredients that could interfere with tadalafil and cause side effects.

Important: Important

Tell your doctor or pharmacist if you're taking any other medicines, including herbal remedies, vitamins or supplements.

9. Common questions

How does tadalafil work?

Tadalafil belongs to a group of medicines called phosphodiesterase 5 (PDE5) inhibitors.

If you have erectile dysfunction, it works by temporarily increasing blood flow to the penis when you get sexually excited.

It helps reduce symptoms of an enlarged prostate gland, such as difficulty peeing or needing to pee urgently, by relaxing the muscles in the prostate and bladder.

It helps pulmonary hypertension by relaxing blood vessels in the chest. This increases blood supply to the lungs and reduces the workload of the heart.

How well does it work for erection problems?

Tadalafil works well for erectile dysfunction.

In general, more than 6 in 10 men say they have harder erections after taking it.

If tadalafil does not work for you, it may be because:

  • you have not waited long enough after taking it before trying to have sex
  • you have waited too long after taking it to have sex
  • the dose is not high enough
  • you're not sexually aroused enough
How long does it take to work?

Tadalafil usually starts to work within 30 to 60 minutes.

It's triggered by sexual stimulation, so you need to be aroused for it to work.

How long will it work for?

You should be able to get an erection at any time between 30 minutes and 36 hours after taking tadalafil. You need to be sexually excited for it to work.

Your erection should go away after you have had sex.

Can I take it as often as I want?

No – do not take tadalafil more than once a day.

How does it compare with other medicines that improve erections?

Other medicines are usually taken on demand, 30 to 60 minutes before sexual activity.

On average, the alternatives to tadalafil work for up to 4 hours. If you take tadalafil, it can be effective for up to 36 hours.

If tadalafil does not work, there are other tablets you could try that work in a similar way, such as:

Only sildenafil (Viagra) is available without prescription.

You can take tadalafil and vardenafil with or without food.

However, you should take sildenafil and avanafil on an empty stomach for fastest effects. Eating a meal which is high in fat may delay the effect of vardenafil.

You could also try a medicine called alprostadil (only available with a prescription). This is a man-made hormone that helps to stimulate blood flow to the penis.

Alprostadil comes as:

  • an injection directly into your penis
  • a small pellet placed inside your urethra (the tube that carries pee from your bladder to the tip of your penis)

If you cannot get erections because of a hormonal problem, your doctor may refer you to an endocrinologist (a doctor who specialises in the treatment of hormonal problems). They may recommend hormone injections to bring your body's levels back to normal.

Are there other treatments that can help erections?

Other treatments for erectile dysfunction include:

  • a vacuum pump
  • psychological treatments
  • penile implants
  • pelvic floor muscle exercises

Some complementary therapies, such as acupuncture, have claimed to treat erectile dysfunction. But there's little evidence they work.

Are there any other medicines for an enlarged prostate?

Tadalafil (5mg only) is the only medicine in it’s group (phosphodiesterase 5 (PDE5) inhibitors) that treats an enlarged prostate.

Other medicines prescribed are:

  • 5-alpha reductase inhibitors, such as finasteride and dutasteride
  • alpha-blockers, such as tamsulosin and alfuzosin
Are there any other medicines for pulmonary hypertension?

If tadalafil does not work, a doctor might recommend sildenafil, which works in a similar way.

Other medicines used to treat pulmonary hypertension are:

  • endothelin receptor antagonists – such as bosentan, ambrisentan and macitentan
  • soluble guanylate cyclase stimulators – such as riociguat
  • prostaglandins – such as epoprostenol, iloprost and treprostinil
  • calcium channel blockers – nifedipine, diltiazem, nicardipine and amlodipine
Is there a herbal alternative to tadalafil?

There are lots of treatments that claim to be a "herbal Cialis". In fact, there's no such thing.

A herbal Cialis has never been approved as a treatment for erectile dysfunction.

Plus, these treatments may be fake or unsafe.

Can women use tadalafil?

Women can use tadalafil for pulmonary hypertension.

There's no good evidence that tadalafil works for women with sexual problems.

Will it affect my fertility?

There's no firm evidence to suggest that taking tadalafil will reduce fertility in either women or men.

However, speak to a pharmacist or doctor before taking it if you're trying to get pregnant.

Will it affect my contraception?

Tadalafil does not affect any type of contraception, including the contraceptive pill and emergency contraception.

Can I drink alcohol with it?

Having 1 beer or glass of wine is not likely to stop or delay tadalafil from working.

But drinking lots of alcohol can make it more difficult to get an erection.

To get the most benefit from tadalafil, do not drink heavily before taking it.

Will recreational drugs affect it?

Taking poppers (amyl nitrite) with tadalafil can have a dangerous effect on your heart.

It can also be potentially dangerous to take tadalafil with:

  • stimulants like MDMA (ecstasy) or cocaine
  • hallucinogens like LSD
  • novel psychoactive substances (which used to be known as legal highs) like mephedrone

Tadalafil has not been properly tested with recreational drugs.

Talk to a doctor if you think you might use any recreational drugs with tadalafil.

Is there any food or drink I need to avoid?

Do not drink grapefruit juice if you're taking tadalafil. It interferes with the way the medicine works.

Can I drive or ride a bike?

Occasionally tadalafil can make you feel dizzy. If this happens to you, do not drive, cycle or use machines or tools until you feel better.

Can lifestyle changes improve erections?

Erectile dysfunction can often be improved if you make changes to your lifestyle, such as:

Can lifestyle changes help symptoms of an enlarged prostate gland?

If you're taking tadalafil to treat symptoms of an enlarged prostate gland, you might be able to help the symptoms by making some simple changes to your lifestyle:

  • drink fewer fizzy drinks and less alcohol, and cut down on caffeine (including tea, coffee and cola) and artificial sweeteners – these can irritate the bladder and make peeing more uncomfortable.
  • drink less in the evening – try to reduce the amount you drink in the evening and avoid drinking anything for 2 hours before you go to bed. This might help you avoid getting up in the night. Make sure you're still drinking enough fluid earlier in the day.
  • empty your bladder – remember to go to the toilet before long journeys if you know you will not be able to reach a toilet easily
  • try "double voiding" – this means waiting a few moments after you have finished peeing before trying to go again. It can help you empty your bladder properly. But take care not to strain or push.
  • check your medicines – check with a doctor whether any medicines you take, such as antidepressants or decongestants, may be making your symptoms worse.
  • eat more fibre – eating more fruit, vegetables and wholegrains helps you avoid constipation, which can put pressure on the bladder and make symptoms of an enlarged prostate worse.