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Cancer drugs A to Z list

Relugolix (Orgovyx)

Relugolix is a type of hormone therapy. You pronounce it as reh-loo-goh-lix. It is also known as Orgovyx.

It is a treatment for advanced prostate cancer that is hormone dependant. Hormone dependent means that the cancer cells need a hormone to grow. 

Find out more about prostate cancer

How do you take relugolix?

You take relugolix as tablets. 

You swallow them whole with a glass of water. You can have the tablets with or without food.

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 take relugolix?

On the first day you take 3 tablets. From day 2 onwards, you take 1 tablet once a day.

Try to take the tablet at the same time each day.

You continue taking relugolix for as long as the treatment is working and you are not experiencing too many side effects.

You might have tests to check your heart, such as an .

Find out more about having an ECG

What are the side effects of relugolix?

Side effects 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

We haven't listed all the side effects here. Talk to your healthcare team if you have any new symptoms that you think might be a side effect of your treatment.

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:

Hot flushes

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.

Diarrhoea

Contact your advice line if you have diarrhoea. For example, in one day you have 2 or more loose bowel movements than usual. If you have a , you might have more output than normal. Your doctor may give you anti diarrhoea medicine to take home with you after treatment.

Try to eat small meals and snacks regularly. It’s best to try to have a healthy balanced diet if you can. You don’t necessarily need to stop eating foods that contain fibre. But if your diet is normally very high in fibre, it might help to cut back on high fibre foods such as beans, nuts, seeds, dried fruit, bran and raw vegetables.

Drink plenty to try and replace the fluid lost. Aim for 8 to 10 glasses per day.

Constipation

is easier to sort out if you treat it early. Drink plenty and eat as much fresh fruit and vegetables as you can. Try to take gentle exercise, such as walking. Tell your healthcare team if you think you are constipated. They can give you a laxative if needed.

Muscle and joint pain

You might feel some pain from your muscles and joints. Speak to your doctor or nurse about what painkillers you can take to help with this.

Tiredness (fatigue)

You might feel very tired and as though you lack energy.

Various things can help you to reduce tiredness and cope with it, for example exercise. Some research has shown that taking gentle exercise can give you more energy. It is important to balance exercise with resting.

Find out more about coping with tiredness (fatigue)

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:

  • a drop in that can cause breathlessness, tiredness and looking pale

  • growth of breast tissue (gynaecomastia) - talk to your doctor if this becomes a problem

  • difficulty sleeping or getting to sleep

  • feeling very low and sad (depression)

  • dizziness

  • headache

  • high blood pressure

  • feeling sick (nausea)

  • sweating more than usual

  • a rash, including raised itchy bumps (hives)

  • a decrease in your sex drive

  • weight gain

  • high blood sugar levels

  • high levels of fatty substances called cholesterol and triglyceride in the blood

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:

  • weakened bones that are fragile and more likely to break (osteoporosis)

  • changes to the way your liver works

  • an allergic reaction needing treatment – signs include fainting, sweating, tiredness, swelling of the face, lips, mouth, tongue or throat

Other side effects

You might have changes to the electrical activity of your heart. There isn't enough information to work out how often this side effect might happen. Tell your healthcare team straightaway if you feel dizzy, faint, like your heart is racing (palpitations) or have chest pain. Very rarely this can cause a heart attack.

What else do you need to know?

Other medicine, food and drink

Cancer drugs can interact with medicines, herbal products, and some food and drinks. We are unable to list all the possible interactions that may happen. An example is grapefruit or grapefruit juice which can increase the side effects of certain drugs.

Tell your healthcare team about any medicines you are taking. This includes vitamins, herbal supplements and over the counter remedies. Also let them know about any other medical conditions or allergies you may have.

Contraception 

This treatment might harm a baby developing in the womb. It is important not to get someone pregnant while you are having treatment and for 2 weeks afterwards. Talk to your doctor or nurse about effective contraception before starting treatment. Let them know straight away if your partner becomes pregnant while you're having treatment.

Loss of fertility

You may not be able to get someone pregnant after treatment with this drug. Talk to your doctor before starting treatment if you think you want to have a baby in the future. You may be able to store sperm before starting treatment.

Treatment for other conditions

If you are having tests or treatment for anything else, always mention your cancer treatment. For example, if you are visiting your dentist.

Last reviewed: 22 Apr 2025

Next review due: 22 Apr 2028

Prostate cancer

Prostate cancer is cancer that starts in the prostate gland. The prostate gland is found at the base of the bladder and is about the size of a walnut.

Side effects of cancer drugs

Cancer drugs have side effects and these can vary from person to person. But there are things that you can do to help you cope.

Coping with cancer

Coping with cancer can be difficult. There is help and support available. Find out about the emotional, physical and practical effects of cancer and how to manage them.

Hormone therapy

Hormone therapy blocks or lowers the amount of hormones in the body to stop or slow down the growth of cancer.

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