Enzalutamide (Xtandi)

Enzalutamide is a type of hormone therapy and is a treatment for prostate cancer.

What is enzalutamide?

It is a treatment for prostate cancer. It is also known as Xtandi. 

You might have it if:

  • you are having androgen deprivation therapy and your cancer has spread to other parts of the body
  • your cancer has spread to parts of the body and other hormone treatments have stopped working, but you have no or mild symptoms and do not need chemotherapy
  • you have already had docetaxel chemotherapy, and your cancer has grown during chemotherapy, or come back after treatment

How does enzalutamide work?

Most prostate cancers need the hormone testosterone to grow. The testicles make almost all testosterone in men. Just above each kidney are 2 adrenal glands, they also make a small amount of testosterone. 

Enzalutamide is a hormone treatment that blocks testosterone from reaching prostate cancer cells. This can slow the growth of the cancer and may shrink it. You might hear it called an androgen receptor blocker (inhibitor).

How do you have enzalutamide?

You take enzalutamide as capsules, once a day. You swallow them whole with a glass of water. You can have the capsules with or without food.

Taking capsules

You must take capsules according to the instructions your doctor or pharmacist gives you.

You should take the right dose, not more or less.

Talk to your healthcare team before you stop taking a cancer drug or if you miss a dose.

How often do you have enzalutamide?

You usually carry on taking enzalutamide for as long as it is working, and the side effects aren’t too bad.


You might have blood tests before starting treatment and during your treatment. They check your general health and might check your levels of blood cells and other substances in the blood.

What are the side effects of enzalutamide?

How often and how severe the side effects are can vary from person to person. They also depend on what other treatment you are having. 

When to contact your team

Your doctor, nurse, or pharmacist will go through the possible side effects. They will monitor you closely during treatment and check how you are at your appointments. Contact your advice line as soon as possible if:

  • you have severe side effects 
  • your side effects aren’t getting any better
  • your side effects are getting worse
Early treatment can help manage side effects better.

We haven't listed all the side effects here. Remember it is very unlikely that you will have all of these side effects, but you might have some of them at the same time.

Common side effects

These side effects happen in more than 10 in 100 people (more than 10%). You might have one or more of them. They include:

Tiredness and weakness (fatigue) during and after treatment

Tiredness and weakness (fatigue) can happen during and after treatment. Doing gentle exercises each day can keep your energy up. Don't push yourself, rest when you start to feel tired and ask others for help.

Hot flushes and sweats

We have some tips for coping with hot flushes in men. This information also includes some of the possible treatments. Talk to your doctor if your hot flushes are hard to cope with. They might be able to prescribe you some medicines.

High blood pressure

Tell your doctor or nurse if you have headaches, nose bleeds, blurred or double vision or shortness of breath. Your nurse will check your blood pressure regularly.


Talk to your team if you fall.

Broken bones (fractures)

This might be due to bone thinning. Speak to your team if you have bone pain or fracture a bone.

Occasional side effects

These side effects happen in between 1 and 10 out of every 100 people (between 1 and 10%). You might have one or more of them. They include:

  • memory problems such as forgetfulness
  • difficulty concentrating
  • headaches
  • breast swelling
  • dry or itchy skin
  • feeling anxious
  • an uncontrollable urge to move a part of the body, usually your legs (restless legs syndrome)
  • build up of fatty substances in the arteries, causing a blockage (ischemic heart disease)
  • taste changes

Rare side effects

These side effects happen in fewer than 1 in 100 people (less than 1%). You might have one or more of them. They include:

  • seizures (fits)
  • increased risk of getting an infection
  • seeing things that are not there (visual hallucination)
  • difficulty thinking clearly, or concentrating

Other side effects

There isn't enough information to work out how often these side effects might happen. You might have one or more of them. They include:

  • bruising, bleeding gums or nosebleeds – contact your team if you have blood in your urine or dark poo
  • feeling or being sick
  • diarrhoea
  • a second cancer
  • fluid build up in different parts of the body such as the face or lips
  • muscle pain, spasms or weakness
  • changes to heart rhythm
  • Posterior reversible encephalopathy syndrome (PRES) - a rare disorder of the nerves causing headache, fits, confusion and changes in vision - contact your health team straight away. This condition is reversible

Coping with side effects

We have more information about side effects and tips on how to cope with them.

What else do I need to know?

Other medicines, food and drink

Cancer drugs can interact with some other medicines and herbal products. Tell your doctor or pharmacist about any medicines you are taking. This includes vitamins, herbal supplements and over the counter remedies.

Contraception and pregnancy

This drug may harm a baby developing in the womb.

It is important not to father a child while you are having treatment. You need to use 2 effective methods of contraception during treatment and for 3 months afterwards. Talk to your doctor or nurse about effective contraception before starting treatment.

Loss of fertility

It is not known whether this treatment affects fertility in people. Talk to your doctor before starting treatment if you think you may want to have a baby in the future.

Treatment for other conditions 

Always tell other doctors, nurses, pharmacists or dentists that you’re having this treatment. For example, if you need treatment for anything else, including teeth problems.

More information about this treatment

For further information about this treatment and possible side effects go to the electronic Medicines Compendium (eMC) website. You can find the patient information leaflet on this website.

You can report any side effect you have to the Medicines Health and Regulatory Authority (MHRA) as part of their Yellow Card Scheme.

  • Electronic Medicines Compendium 
    Accessed May 2021

  • Toxicity, Adverse Events, and Quality of Life Associated with the Treatment of Metastatic Castration-Resistant Prostate Cancer

    S Tonyali and others 

    Current Urology, 2016. Volume 10, pages 169–173

Last reviewed: 
22 Oct 2021
Next review due: 
22 Oct 2024

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