Olaparib (Lynparza)

Olaparib is a targeted drug Open a glossary item. It is used for a number of cancers. You might have it by itself or with another cancer drug such as bevacizumab.

You might also have it as part of a clinical trial Open a glossary item.

It is for people who have a change in the BRCA1 Open a glossary item or BRCA2 Open a glossary item gene. Not everyone may be tested for these gene changes before having olaparib.

For prostate cancer you have it if your cancer comes back while having hormone therapy Open a glossary item.

Doctors also use olaparib for people whose cancer has come back and it had responded well to a platinum chemotherapy drug Open a glossary item. This maintenance treatment after chemotherapy.

Maintenance treatment aims to stop cancer from coming back or growing for as long as possible. This may not be suitable for everyone. Ask your doctor whether this treatment is suitable for you.

How does olaparib work?

Olaparib is a targeted drug called a PARP inhibitor Open a glossary item. PARP is a protein that helps damaged cells to repair themselves. Olaparib stops PARP working.

Some cancer cells rely on PARP to keep their DNA Open a glossary item healthy. This includes cancer cells with a change in the BRCA genes. So, when olaparib stops PARP from repairing DNA damage, the cancer cells die.

How do you have olaparib?

Olaparib comes as tablets.

You must take tablets according to the instructions your doctor or pharmacist gives you. It is important not to mix taking tablets and capsules.

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

Talk to your specialist or advice line before you stop taking a cancer drug.

How often do you have olaparib?

You usually take them twice a day, 12 hours apart. You swallow them whole with or without food.

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

For certain types of cancer such as ovarian cancer, you may stop taking olaparib after 2 years if there are no signs of cancer on any scan Open a glossary item


You have blood tests before and during your treatment. They check your levels of blood cells and other substances in the blood. They also check how well your liver and kidneys are working.

Depending on your cancer type you might have regular CT scans to check how well olaparib is working.

What are the side effects of olaparib?

Side effects can vary from person to person. They also depend on what other treatments you're having. 

When to contact your team

Your doctor, nurse or pharmacist will go through the possible side effects. They will monitor you 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. 

Contact your advice line immediately if you have signs of infection, including a temperature above 37.5C or below 36C.

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:

Increased risk of infection

Increased risk of getting an infection is due to a drop in white blood cells. Symptoms include a change in temperature, aching muscles, headaches, feeling cold and shivery and generally unwell. You might have other symptoms depending on where the infection is.

Infections can sometimes be life threatening. You should contact your advice line urgently if you think you have an infection. 

Bruising and bleeding

This is due to a drop in the number of platelets in your blood. These blood cells help the blood to clot when we cut ourselves. You may have nosebleeds or bleeding gums after brushing your teeth. Or you may have lots of tiny red spots or bruises on your arms or legs (known as petechiae).

Breathlessness and looking pale

You might be breathless and look pale due to a drop in red blood cells. This is called anaemia.

Tiredness and weakness (fatigue)

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.

Let your doctor or nurse know if you have headaches. They can give you painkillers. Don’t drive or operate machinery if you feel dizzy.

Feeling or being sick

Feeling or being sick is usually well controlled with anti sickness medicines. Avoiding fatty or fried foods, eating small meals and snacks, drinking plenty of water, and relaxation techniques can all help.

Tell your doctor or nurse if you are feeling sick as there are medication they can give to help.


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 stoma Open a glossary item, 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.

Loss of appetite

You might lose your appetite for various reasons while having cancer treatment. Sickness, taste changes or tiredness can put you off food and drinks.


Contact your doctor or pharmacist if you have indigestion or heartburn. They can prescribe medicines to help.

Taste changes 

Taste changes may make you go off certain foods and drinks. You may also find that some foods taste different from usual or that you prefer to eat spicier foods. Your taste gradually returns to normal a few weeks after your treatment finishes.


Let your doctor or nurse know if you have headaches. They can give you painkillers.


This drug might make you feel dizzy. Don’t drive or operate machinery if you have this.


You might develop a cough. This could be due to inflammation of the lungs (pneumonitis), but this is rare. Let your doctor or nurse know straight away if you suddenly develop a cough.

Shortness of breath

You might feel short of breath. Talk to your doctor or nurse if you do.

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:

  • changes to how your kidney works, you don't usually have any symptoms but it shows up in blood tests
  • sore mouth
  • pain in upper part of stomach
  • skin rash

Rare side effects

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

  • secondary cancer
  • inflammation of the lungs
  • an allergic reaction that can cause a rash, shortness of breath, redness or swelling of the face and dizziness - some allergic reactions can be life threatening, alert your nurse or doctor if notice any of these symptoms
  • swelling under the skin

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, foods 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.

Pregnancy and contraception

This drug may harm a baby developing in the womb. It is important not to become pregnant or father a child while you are having treatment. You should use to 2 different types of contraception. It is best if one is a non hormonal type. You use them before starting treatment and during treatment. Women should continue using contraception for 1 month after taking the last tablet. For men it is for 3 months after the last tablet.


Don’t breastfeed during this treatment because the drug may come through into your breast milk.

Doctors usually advise that you don’t breastfeed during this treatment and for 1 month after taking the last tablet.

loss of fertility

It is not known whether this treatment affects fertility Open a glossary item 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

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


Don’t have immunisations with live vaccines while you’re having treatment and for up to 12 months afterwards. The length of time depends on the treatment you are having. Ask your doctor or pharmacist how long you should avoid live vaccinations.

In the UK, live vaccines include rubella, mumps, measles, BCG, yellow fever and one of the shingles vaccines called Zostavax.

You can have:

  • other vaccines, but they might not give you as much protection as usual
  • the flu vaccine (as an injection)
  • the coronavirus (COVID-19) vaccine - talk to your doctor or pharmacist about the best time to have it in relation to your cancer treatment

Members of your household who are aged 5 years or over are also able to have the COVID-19 vaccine. This is to help lower your risk of getting COVID-19 while having cancer treatment and until your immune system Open a glossary item recovers from treatment.

Contact with others who have had immunisations - You can be in contact with other people who have had live vaccines as injections. Avoid close contact with people who have recently had live vaccines taken by mouth (oral vaccines) such as the oral typhoid vaccine. Sometimes people who have had the live shingles vaccine can get a shingles type rash. If this happens they should keep the area covered.

If your immune system is severely weakened, you should avoid contact with children who have had the flu vaccine as a nasal spray as this is a live vaccine. This is for 2 weeks following their vaccination.

Babies have the live rotavirus vaccine. The virus is in the baby’s poo for about 2 weeks and could make you ill if your immunity is low. Get someone else to change their nappies during this time if you can. If this isn't possible, wash your hands well after changing their nappy.

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.

Related links