Niraparib (Zejula®) is a targeted therapy drug used to treat some types of ovarian, fallopian tube or primary peritoneal cancer. It may sometimes be used to treat other cancers. It is best to read this information with our general information about the type of cancer you have.
Niraparib is not suitable for everyone. Your cancer doctor can tell you if it is suitable for you.
Niraparib belongs to a group of targeted therapy drugs called cancer growth inhibitors. It can also be 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 doctor will talk to you about this treatment and its possible side effects before you agree (consent) to have treatment.
Niraparib is given as capsules. This means you can take it at home.
During treatment you usually see a cancer doctor, a cancer nurse or specialist nurse, and a 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 see a doctor or nurse before you have treatment. They will ask you how you have been feeling. If your blood results are okay, the pharmacist will prepare your targeted therapy. Your nurse will tell you when your treatment is likely to be ready.
Taking niraparib capsules
You take niraparib once a day. Your doctor, nurse or pharmacist will tell you how many capsules to take. Always take them exactly as you are told to. This is important to make sure they work as well as possible for you.
Try to take the capsules at the same time each day. Swallow the capsules whole with water. Do not chew, dissolve or open them. If you forget to take the capsules, 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 at bedtime may help control sickness.
Other things to remember about your capsules:
- Wash your hands after taking your capsules.
- Other people should avoid direct contact with the drugs.
- Keep them in the original package and at room temperature, away from heat and direct sunlight.
- Keep them safe and out of sight and reach of children.
- If you are sick just after taking the capsules, contact the hospital. Do not take another dose.
- If your treatment is stopped, return any unused capsules to the pharmacist.
Your course of treatment
We explain the most common side effects of this treatment here. We also include some less common side effects.
You may get some of the side effects we mention, but you are unlikely to get all of them. If you are also having treatment with other cancer drugs, you may have some side effects that we have not listed here. Always tell your doctor, nurse or pharmacist about any side effects you have.
Your doctor can give you drugs to help control some side effects. It is important to take them exactly as your nurse or pharmacist explains. This means they will be more likely to work for you. Your nurse will give you advice about managing your side effects. After your treatment is over, most side effects start to improve.
Serious and life-threatening side effects
Some cancer treatments can cause severe side effects. Rarely, these may be life-threatening. Your cancer doctor or nurse can explain the risk of these side effects to you.
Contact the hospital
Your nurse will give you telephone numbers for the hospital. If you feel unwell or need advice, you can call them at any time of the day or night. Save these numbers in your phone or keep them somewhere safe.
We cannot list every side effect for this treatment. There are some rare side effects that are not listed. You can visit the electronic Medicines Compendium (eMC) for more detailed information.
Some people have an allergic reaction while having this treatment. Signs of a reaction can include:
- feeling hot or flushed
- a skin rash
- feeling dizzy
- a headache
- feeling breathless.
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.
Risk of infection
This treatment can reduce the number of white blood cells in your blood. These cells fight infection. If the number of white blood cells is low, you are more likely to get an infection. A low white blood cell count is sometimes 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. Contact the hospital straight away on the 24-hour contact number you have been given if:
- your temperature goes over 37.5°C (99.5°F)
- you suddenly feel unwell, even with a normal temperature
- you have symptoms of an infection
- your temperature goes below 36°C (96.8°F).
Symptoms of an infection include:
- feeling shivery and shaking
- a sore throat
- a cough
- needing to pass urine (pee) a lot, 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 needed, your doctor may reduce or delay your treatment for a short time, until your cell count increases.
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:
- bleeding gums
- heavy periods
- blood in your urine (pee) or stools (poo)
- tiny red or purple spots on the skin that may look like a rash.
Tell your doctor if you have any unexplained bruising or bleeding. 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 have symptoms such as:
- pale skin
- lack of energy
- feeling breathless
- feeling dizzy and light-headed.
Tell your doctor or nurse if you have these symptoms.
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
Niraparib 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.
Niraparib can make you feel or be sick. Taking your capsules 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.
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 for advice. Your doctor can give you drugs called laxatives to help.
This treatment may cause diarrhoea. Diarrhoea means passing more stools (poo) than is usual for you, or having watery or loose stools. If you have a stoma, it will be more active than usual.
If you have diarrhoea:
- try to drink at least 2 litres (3½ pints) of fluids each day
- avoid alcohol, caffeine, milk products, high-fat foods and high-fibre foods
- contact the hospital for advice.
Loss of appetite
This treatment can affect your appetite. Do not worry if you do not eat much for a day or two. But if your appetite does not come back after a few days, tell your nurse or dietitian. They will give you advice. They may give you food or drink supplements.
Tummy pain and indigestion
Changes to your taste
You may get a bitter or metal taste in your mouth. Sucking sugar-free sweets may help with this. Some foods may taste different or have no taste. Try different foods to find out what tastes best to you. Taste changes usually get better after treatment finishes. Your nurse can give you more advice.
Feeling tired is a common side effect. Try to pace yourself and plan your day so you have time to rest. Gentle exercise, like short walks, can give you more energy. If you feel sleepy, do not drive or operate machinery.
Sleep problems and mood changes
You may have difficulty sleeping while you are taking niraparib. Some people taking niraparib 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.
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.
This treatment may cause headaches. If you have headaches, tell your doctor. They may give you painkillers to help.
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 niraparib. It is not usually serious. But you should contact your doctor straight away so they can check.
Sore mouth and throat
This treatment may cause a 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 sometimes help relieve mouth or throat pain.
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.
Build-up of fluid
Your ankles and legs may swell because of fluid building up. Tell your doctor or nurse if this happens.
Effects on the lungs
This treatment can cause changes to the lungs. Tell your doctor if you develop:
- a cough
You should also tell them if any existing breathing problems get worse.
Some cancer drugs can increase the risk of developing other types of cancer or leukaemia later in life. This is rare. Your doctors will consider the small increase in risk of this happening against the benefit of the drug in treating your cancer.
Effects on the nervous system
This treatment can affect the nervous system. Very rarely, it can cause a condition called PRES (posterior reversible encephalopathy syndrome). Symptoms include:
- changes in your eyesight
- fits (seizures).
Contact the hospital straight away if you have any of these symptoms. It is important not to drive or operate machinery if you notice these effects.
Blood clot risk
Cancer and some cancer treatments can increase the risk of a blood clot. Symptoms of a blood clot include:
- throbbing pain, redness or swelling in a leg or arm
- suddenly feeling breathless or coughing
- sharp chest pain, which may be worse when you cough or take a deep breath.
If you have any of these symptoms, contact the hospital straight away on the 24-hour contact number you have been given. If you cannot get through to your doctor, call the NHS urgent advice number on 111.
A blood clot is serious, but it can be treated with drugs that thin the blood (anticoagulants). Your doctor or nurse can give you more information.
You can help reduce the risk of developing a blood clot by:
- staying active during treatment
- drinking plenty of fluids, especially water.
You may be given anticoagulants to help prevent a clot.
Vaccinations can reduce your risk of getting certain infections. Your doctor or nurse may talk to you about having vaccinations.
Doctors usually recommend that people with cancer have a flu vaccination and a coronavirus vaccination. These are both inactivated vaccinations that can help reduce the risk of infection. People with weak immune systems can have these, as they are not live vaccinations.
If your immune system is weak, you need to avoid live vaccinations. This is because they can make you unwell. Live vaccines, such as shingles, contain a very weak version of the illness they are vaccinating you against. Your cancer doctor or GP can tell you more about live and inactivated vaccinations.
Some medicines can affect how this treatment works or be harmful when you are having it. Always tell your cancer doctor about any drugs you are taking or planning to take, such as:
- medicines you have been prescribed
- medicines you buy in a shop or chemist
- vitamins, herbal drugs and complementary therapies.
Tell other doctors, pharmacists or dentists who prescribe or give you medicines that you are having this cancer treatment.
You can visit the electronic Medicines Compendium (eMC) for more detailed information about your treatment.
Your doctor will advise you not to get pregnant or make someone pregnant while having this treatment. The drugs may harm a developing baby. It is important to use contraception during your treatment and for a while after treatment finishes. Your doctor, nurse or pharmacist can tell you more about this.
You are advised not to breastfeed while having this treatment, or for some time after treatment finishes. This is because the drugs could be passed to the baby through breast milk.
Your doctor or nurse can give you more information.
Lactose and tartrazine
Niraparib capsules contain lactose. They also contain a food colouring called tartrazine. If you have an intolerance to some sugars, or are allergic to tartrazine, talk to your doctor before you start this treatment.
Medical and dental treatment
If you need medical treatment for any reason other than cancer, always tell the doctors and nurses you are having cancer treatment. Give them the contact details for your cancer doctor so they can ask for advice.
If you think you need dental treatment, talk to your cancer doctor or nurse. Always tell your dentist you are having cancer treatment.
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.