Niraparib

Niraparib is used to treat ovarian cancer, fallopian tube cancer and primary peritoneal cancer. It may sometimes be used to treat other cancers. It is best to read the information about this drug with our general information about targeted therapy drugs and the type of cancer you have. 

Niraparib belongs to a group of targeted therapy drugs called cancer growth inhibitors. It is also known as a PARP inhibitor. PARPs are proteins that help damaged cells repair themselves.

Niraparib blocks (inhibits) how PARP proteins work. Without PARP proteins, cancer cells may become too damaged to survive, and die. 

Your cancer doctor will talk to you about this treatment and its possible side effects before you agree (consent) to have treatment.

More information about this treatment

This information is correct at time of publishing. But sometimes the types of cancer this treatment is used for, or treatment side effects, may change between revision dates.

You can talk to your cancer team if you want more detailed information about this treatment. Or visit the electronic Medicines Compendium (eMC) website, which has patient information leaflets (PIL) for individual drugs.

How niraparib is given

Niraparib is given as tablets or capsules. This means you can take it at home. 

During treatment, you usually see a:

  • cancer doctor
  • cancer nurse or specialist nurse
  • specialist pharmacist. 

This is who we mean when we mention doctor, nurse or pharmacist in this information.

You will have regular blood tests during treatment. This is to check that your kidneys are working and that your blood cells are at a safe level to have treatment. You will also have regular blood pressure checks. 

You will speak to a doctor, nurse or pharmacist regularly during treatment. They will talk to you about your test results and ask how you have been feeling.  

They will give you the capsules or tablets to take home. They may also give you anti-sickness drugs and other medicines to take home. Take all your capsules or tablets exactly as they have been explained to you. This is important to make sure they work as well as possible for you.

Your course of treatment

You usually keep taking niraparib for as long as it is effective and any side effects are manageable. If you want to stop taking niraparib for any reason, talk to your doctor first.

Your doctor, nurse or pharmacist will discuss your treatment plan with you. They may give you a copy of the treatment plan to take home.

Taking niraparib

You take niraparib once a day. 

You can take it with or without food. Try to take it at the same time each day. Swallow the capsules or tablets whole with water. Do not chew, dissolve, break or open them. If you forget to take niraparib, do not take a double dose. Take your next dose at the usual time and let your doctor or nurse know.

Feeling sick can be a side effect of niraparib. Taking your capsules or tablets at bedtime may help control sickness.

Other things to remember about your capsules or tablets:

  • Keep them in the original package and at room temperature, away from moisture, heat and direct sunlight.
  • Keep them safe, somewhere children cannot see or reach them.
  • If you are sick just after taking the capsules or tablets, contact the hospital. Do not take another dose.
  • If your treatment is stopped, return any unused capsules or tablets to the pharmacist.

About side effects

We explain the most common side effects of this treatment here. We also include some that are less common. 

You may get some of the side effects we mention, but you are unlikely to get all of them. And you may have some side effects, including rarer ones, that we have not listed here. 

Other cancer treatments may cause different side effects. If you are also having other cancer treatment, you may have other side effects.

Always tell your doctor, nurse or pharmacist about any side effects you have. They can give you: 

  • drugs to help control some side effects 
  • advice about managing side effects. 

It is important to take any drugs exactly as explained. This means they will be more likely to work for you.

Serious and life-threatening side effects

Some cancer treatments can cause serious side effects. Sometimes, these may be life-threatening. Your doctor, nurse or pharmacist can explain the risk of these side effects to you.

Contact the hospital

Your doctor, nurse or pharmacist will give you 24-hour contact numbers for the hospital. If you feel unwell or need advice, you can call at any time of the day or night. Save these numbers in your phone or keep them somewhere safe.

Side effects while treatment is being given

Some people have side effects while taking this treatment, or shortly after.

Allergic reaction

Some people have an allergic reaction while having this treatment. Signs of a reaction can include:

  • feeling hot or flushed 
  • a skin rash
  • itching
  • shivering
  • feeling dizzy
  • a headache
  • feeling breathless or wheezy
  • swelling of your face or lips.

If you feel unwell or have any of these signs, tell a doctor or nurse straight away. Do not take any more of this treatment until you have spoken to them.

Common side effects

Risk of infection

This treatment can reduce the number of white blood cells in your blood. These cells fight infection. If your white blood cell count is low, you may be more likely to get an infection. A low white blood cell count is called neutropenia.

An infection can be very serious when the number of white blood cells is low. It is important to get any infection treated as soon as possible. If you have any of the following symptoms, contact the hospital straight away on the 24-hour number:

  • a temperature above 37.5°C 
  • a temperature below 36°C
  • you feel unwell, even with a normal temperature
  • you have symptoms of an infection.

Symptoms of an infection include:

  • feeling shivery and shaking
  • a sore throat
  • a cough
  • breathlessness
  • diarrhoea
  • needing to pass urine (pee) often, or discomfort when you pass urine.

It is important to follow any specific advice your cancer treatment team gives you.

You will have regular blood tests during treatment. If your white blood cell count is low, your doctor may stop your treatment for a short time, until your cell count increases. Sometimes they will reduce the dose of your treatment.

Bruising and bleeding

This treatment can reduce the number of platelets in your blood. Platelets are cells that help the blood to clot.

If the number of platelets is low, you may bruise or bleed easily. You may have:

  • nosebleeds
  • bleeding gums
  • heavy periods
  • blood in your urine (pee) or stools (poo)
  • tiny red, brown or purple spots that may look like a rash – these spots can be harder to see if you have black or brown skin. 

If you have any unexplained bruising or bleeding, contact the hospital straight away on the 24-hour number. You may need a drip to give you extra platelets. This is called a platelet transfusion.

Anaemia (low number of red blood cells)

This treatment can reduce the number of red blood cells in your blood. Red blood cells carry oxygen around the body. If the number of red blood cells is low, this is called anaemia. You may feel:

  • very low in energy
  • breathless 
  • dizzy and light-headed. 

If you have these symptoms, contact the hospital straight away on the 24-hour number. You may need treatment for anaemia. If you are very anaemic, you may need a drip to give you extra red blood cells. This is called a blood transfusion.

High blood pressure

This treatment may cause high blood pressure. Tell your doctor or nurse if you have ever had problems with high blood pressure, or if you take drugs for this. Your nurse will check your blood pressure regularly during treatment. Let them know if you have any headaches.

Feeling sick

This treatment can make you feel or be sick. Taking your capsules or tablets at bedtime may help control sickness. Your doctor can also give you anti-sickness drugs to help prevent or control sickness. Take the drugs exactly as your nurse or pharmacist tells you. 

If you feel sick, take small sips of fluids and eat small amounts often. It is important to drink enough fluids. If you continue to feel sick, or are sick (vomit) more than once in 24 hours, contact the hospital as soon as possible. They will give you advice. Your doctor or nurse may change the anti-sickness drug to one that works better for you.

Constipation

This treatment can cause constipation. Constipation means that you are not able to pass stools (poo) as often as you normally do. It can become difficult or painful. Here are some tips that may help:

  • Drink at least 2 litres (3½ pints) of fluids each day.
  • Eat high-fibre foods, such as fruit, vegetables and wholemeal bread.
  • Do regular gentle exercise, like going for short walks.

If you have constipation, contact the hospital on the 24-hour number for advice. They can give you drugs called laxatives to help. 

If you have not been able to pass stools for over 2 days and are being sick, contact the 24-hour number straight away. 

Diarrhoea

This treatment may cause diarrhoea. Diarrhoea means passing more stools (poo) than is normal for you, or having watery or loose stools. You may also have stomach cramps. If you have a stoma, it may be more active than usual. 

If you are passing loose stools 3 or more times a day and this is not normal for you, contact the hospital as soon as possible on the 24-hour number. Follow the advice they give you about:

  • taking anti-diarrhoea medicines 
  • drinking enough fluids to keep you hydrated and to replace lost salts and minerals
  • any changes to your diet that might help. 

They might also ask you for a specimen of your stool to check for infection.

Loss of appetite

This treatment can affect your appetite. Don’t worry if you do not eat much for 1 or 2 days. But if your appetite does not come back after a few days, or if you are losing weight, tell your doctor, nurse or pharmacist. They can give you advice. They may give you food or drink supplements. Or they may suggest changes to your diet or eating habits to help.

Tummy pain

You may get pain in your tummy (abdomen), or have indigestion. Your doctor, nurse or pharmacist can give you advice or treatment to help. Contact the hospital straight away on the 24-hour number if your symptoms do not go away, or get worse.

Changes to your taste

Some foods may taste different or have no taste. Try different foods to find out what tastes best to you. You may also get a bitter or metallic taste in your mouth. Your doctor, nurse or pharmacist can give you advice. It might help to try:

  • sucking sugar-free sour or boiled sweets
  • eating cold foods
  • eating sharp-tasting fresh fruit.

Taste changes usually get better after treatment ends. We have more information about coping with changes to taste.

Feeling tired (fatigue)

Feeling tired is a common side effect. Try to pace yourself and plan your day so you have time to rest between activities.

Being physically active can help to manage tiredness and give you more energy. It also:

  • helps you sleep better
  • reduces stress
  • improves your bone health.

If you feel sleepy, do not drive or operate machinery.

Sleep problems and mood changes

You may have difficulty sleeping while you are taking this treatment. Some people may become low in mood or anxious. Talk to your doctor or specialist nurse if you notice any of these side effects.

Memory and concentration

You may notice changes in your memory. You may also find it harder to concentrate. To help you remember things, try using: 

  • a notebook
  • notes on your phone 
  • a calendar.

If you have problems concentrating, you should not drive or operate machinery.

Dizziness

You may feel dizzy during this treatment. Tell your doctor or nurse if this is difficult to cope with. If you feel dizzy, do not drive or operate machinery.

Headaches

This treatment may cause headaches. If you have headaches, tell your doctor, nurse or pharmacist. They can give you advice about painkillers that may help. Tell them if the headache does not get better, or gets worse.

Back, joint or muscle pain

You may get pain in your back, muscles or joints. If this happens, tell your doctor so they can give you painkillers. Tell them if the pain does not get better. If you have painkillers you would like to use at home, check with your doctor, nurse or pharmacist whether they are suitable for you. 

If you have back, muscle or joint pain, try taking warm baths. Plan your activities to include regular rests.

Effects on the heart

You may feel your heart is beating too fast or your heartbeat is not regular. This is a common side effect of this treatment. It is not usually serious. But you should contact your doctor straight away so they can check.

Less common side effects

Sore mouth and throat

This treatment may cause a dry or sore mouth and throat. You may also get mouth ulcers. This can make you more likely to get a mouth or throat infection. Use a soft toothbrush to clean your teeth or dentures in the morning, at night and after meals.

If your mouth or throat is sore:

  • tell your nurse or doctor – they can give you a mouthwash or medicines to help
  • try to drink plenty of fluids
  • avoid alcohol, tobacco and foods that irritate your mouth and throat.

Sucking ice chips may help to relieve mouth or throat pain.

Skin changes

This treatment can cause a mild rash. It may also make your skin sensitive to sunlight. If you are out in the sun, use a sun cream with a high sun protection factor (at least SPF 30) to protect your skin. Cover up with clothing and a hat in the sun. Tell your doctor or nurse if you have any skin changes. They can prescribe creams and drugs to help.

Eye problems

This treatment may make your eyes feel sore, red and itchy (conjunctivitis). Your doctor, nurse or pharmacist can prescribe eye drops to help. It is important to use these as instructed.

Fluid build-up

Your ankles and legs may swell because of fluid building up. Tell your doctor, nurse or pharmacist if this happens.

Effects on the lungs

This treatment can cause changes to the lungs. Tell your doctor, nurse or pharmacist if you develop: 

  • a cough that does not go away
  • wheezing
  • breathlessness.

You should also tell them if any existing breathing problems get worse. You may have tests to check your lungs.

Second cancer

Some cancer drugs can increase the risk of developing other types of cancer or leukaemia later in life. This is rare. The benefits of treatment usually far outweigh this risk. Your doctor can talk to you about this.

Effects on the brain

Rarely, this treatment causes a brain condition that can be serious. You can make a full recovery from this. But it must be diagnosed and treated quickly.

This condition can cause:

  • a headache that does not get better
  • drowsiness or confusion
  • changes in eyesight
  • fits (seizures).

If you have any of these symptoms, it is important to either:

  • contact the hospital straight away on the 24-hour number 
  • go to the hospital straight away. 

You should not drive yourself to hospital.

Other information

Blood clot risk

Cancer and some cancer treatments can increase the risk of a blood clot. Contact the hospital straight away on the 24-hour number if you have any of these symptoms during or after treatment:

  • throbbing pain or swelling in a leg or arm
  • reddening of the skin in the area – if you have black or brown skin, this can be harder to notice, but the skin might become darker
  • suddenly feeling breathless or coughing.

Always call 999 if you have:

  • chest pain
  • difficulty breathing.

A blood clot is serious, but it can be treated with drugs called anticoagulants. These thin the blood. Your doctor, nurse or pharmacist can give you more information about preventing and treating blood clots.

Vaccinations

Doctors usually recommend that people with cancer have vaccinations for flu and for coronavirus (covid). These help reduce your risk of serious illness from these infections. Most people can have these vaccines, including people with weak immune systems.

If your immune system is weak, you should not have live vaccinations. Live vaccines can make you unwell because they contain a very weak version of the illness they will protect you against. Live vaccines include Zostavax®, which is a shingles vaccine, and the yellow fever vaccine.

It is important to ask your doctor, nurse or pharmacist for advice about having vaccinations. They can explain what vaccines are right for you and when it is best to have them.

Lactose

This treatment may contain lactose. If you have a lactose allergy or intolerance, ask your doctor, nurse or pharmacist for more information.

Fertility

Some cancer drugs can affect whether you can get pregnant or make someone pregnant. If you are worried about this, it is important to talk with your doctor before you start treatment.

Contraception

Your doctor, nurse or pharmacist will advise you not to get pregnant or make someone pregnant while having this treatment and for some time afterwards. The drugs may harm a developing baby. It is important to use contraception to prevent pregnancy. Follow their advice about:

  • what types of contraception to use 
  • how long after treatment you should continue to use contraception. 

Breastfeeding

You are advised not to breastfeed while having this treatment, or for some time after treatment ends. This is because the drugs could be passed to the baby through breast milk. 

Your doctor, nurse or pharmacist can give you more information.

Medical and dental treatment

If you need medical treatment for any reason other than cancer, always tell the healthcare professional that you are having cancer treatment. Give them the contact details for your cancer doctor or cancer team so they can ask for advice.

If you have appointments with a dentist, always tell them you are having cancer treatment. Talk to your cancer team before you have any dental treatment.

Other medicines

Some medicines can affect how this treatment works or be harmful while you are having it. Always tell your cancer doctor, nurse or pharmacist about any drugs you are taking or planning to take, such as: 

About our information

  • Reviewers

    This information has been written, revised and edited by Macmillan Cancer Support’s Cancer Information Development team. It has been reviewed by expert health professionals and people living with cancer.

    Our cancer information has been awarded the PIF TICK. Created by the Patient Information Forum, this quality mark shows we meet PIF’s 10 criteria for trustworthy health information.

The language we use

We want everyone affected by cancer to feel our information is written for them.

We want our information to be as clear as possible. To do this, we try to:

  • use plain English
  • explain medical words
  • use short sentences
  • use illustrations to explain text
  • structure the information clearly
  • make sure important points are clear.

We use gender-inclusive language and talk to our readers as ‘you’ so that everyone feels included. Where clinically necessary we use the terms ‘men’ and ‘women’ or ‘male’ and ‘female’. For example, we do so when talking about parts of the body or mentioning statistics or research about who is affected.

You can read more about how we produce our information here.

Date reviewed

Reviewed: 01 November 2023
|
Next review: 01 November 2025
Trusted Information Creator - Patient Information Forum
Trusted Information Creator - Patient Information Forum

Our cancer information meets the PIF TICK quality mark.

This means it is easy to use, up-to-date and based on the latest evidence. Learn more about how we produce our information.