Niraparib Side Effects

Medically reviewed by Drugs.com. Last updated on Feb 17, 2025.

Applies to niraparib: oral tablet.

Precautions

It is very important that your doctor check your progress at regular visits. This will allow your doctor to see if the medicine is working properly and to decide if you should continue to take it. Blood tests may be needed to check for unwanted effects.

Using this medicine while you are pregnant can harm your unborn baby. If you are a woman who can get pregnant, your doctor may do tests to make sure you are not pregnant before starting treatment. Use an effective form of birth control to keep from getting pregnant during treatment and for at least 6 months after the last dose of this medicine. If you think you have become pregnant while using the medicine, tell your doctor right away.

This medicine may cause bone marrow problems, including myelodysplastic syndrome or acute myeloid leukemia. Check with your doctor right away if you have a fever, blood in the urine or stool, chills, unusual bleeding, bruising, tiredness, or weakness, or weight loss.

Niraparib can temporarily lower the number of white blood cells in your blood, increasing the chance of getting an infection. It can also lower the number of platelets, which are necessary for proper blood clotting. If this occurs, there are certain precautions you can take, especially when your blood count is low, to reduce the risk of infection or bleeding:

• If you can, avoid people with infections. Check with your doctor immediately if you think you are getting an infection or if you get a fever or chills, cough or hoarseness, lower back or side pain, or painful or difficult urination.
• Check with your doctor immediately if you notice any unusual bleeding or bruising, black, tarry stools, blood in the urine or stools, or pinpoint red spots on your skin.
• Be careful when using a regular toothbrush, dental floss, or toothpick. Your medical doctor, dentist, or nurse may recommend other ways to clean your teeth and gums. Check with your medical doctor before having any dental work done.
• Do not touch your eyes or the inside of your nose unless you have just washed your hands and have not touched anything else in the meantime.
• Be careful not to cut yourself when you are using sharp objects such as a safety razor or fingernail or toenail cutters.
• Avoid contact sports or other situations where bruising or injury could occur.

If you plan to have children, talk with your doctor before using this medicine. Some men using this medicine have become infertile (unable to have children).

Your doctor will check your blood pressure on a regular basis while you are using this medicine. You might need to monitor your blood pressure at home. Tell your doctor right away if you have a severe headache, lightheadedness, or changes in your vision.

Check with your doctor right away if you have agitation, back pain, blurred vision, change in consciousness, confusion, dizziness, drowsiness, fever, hallucinations, headache, irritability, loss of consciousness, mood or mental changes, seizures, stiff neck, unusual tiredness or weakness, or vomiting. These may be symptoms of a serious nervous system problem called posterior reversible encephalopathy syndrome (PRES).

Do not take other medicines unless they have been discussed with your doctor. This includes prescription or nonprescription (over-the-counter [OTC]) medicines and herbal or vitamin supplements.

Serious side effects of niraparib

Along with its needed effects, niraparib may cause some unwanted effects. Although not all of these side effects may occur, if they do occur they may need medical attention.

Check with your doctor immediately if any of the following side effects occur while taking niraparib:

Other side effects of niraparib

Some side effects of niraparib may occur that usually do not need medical attention. These side effects may go away during treatment as your body adjusts to the medicine. Also, your health care professional may be able to tell you about ways to prevent or reduce some of these side effects.

Check with your health care professional if any of the following side effects continue or are bothersome or if you have any questions about them:

For healthcare professionals

Applies to niraparib: oral capsule, oral tablet.

General adverse events

The most commonly reported adverse reactions (incidence 20% or greater) were

decreased hemoglobin (85%), decreased platelet count (82%), nausea (74%), decreased white blood cell count (66%), thrombocytopenia (61%), fatigue/asthenia (57%), decreased absolute neutrophil count (53%), anemia (50%), constipation (40%), increased AST (36%), vomiting (34%), abdominal pain/distention (33%), neutropenia (30%), increased ALT (28%), insomnia (27%), headache (26%), decreased appetite (25%), nasopharyngitis (23%), rash (21%), diarrhea (20%), dyspnea (20%), hypertension (20%), and mucositis/stomatitis (20%).^[Ref]

Hematologic

• Very common (10% or more): Decreased hemoglobin (85%), decreased platelet count (82%), decreased white blood cell count (66%), thrombocytopenia (61%), decreased absolute neutrophil count (53%), anemia (50%), neutropenia (30%), leukopenia (17%)^[Ref]

Gastrointestinal

• Very common (10% or more): Nausea (74%), constipation (40%), vomiting (34%), abdominal pain/distention (33%), diarrhea (20%), mucositis/stomatitis (20%), dyspepsia (18%), dry mouth (10%)^[Ref]

Other

• Very common (10% or more): Fatigue/asthenia (57%)
• Common (1% to 10%): Peripheral edema^[Ref]

Hepatic

• Very common (10% or more): Increased AST (36%), Increased ALT (28%), AST/ALT elevation (10%)
• Common (1% to 10%): Increased gamma-glutamyl transferase, increased blood alkaline phosphatase^[Ref]

Psychiatric

• Very common (10% or more): Insomnia (27%), anxiety (11%)
• Common (1% to 10%): Depression^[Ref]

Nervous system

• Very common (10% or more): Headache (26%), dizziness (18%), dysgeusia (10%)^[Ref]

Metabolic

• Very common (10% or more): Decreased appetite (25%)
• Common (1% to 10%): Hypokalemia, decreased weight^[Ref]

Respiratory

• Very common (10% or more): Nasopharyngitis (23%), dyspnea (20%), cough (16%)
• Common (1% to 10%): Bronchitis, epistaxis^[Ref]

Dermatologic

• Very common (10% or more): Rash (21%)^[Ref]

Cardiovascular

• Very common (10% or more): Hypertension (20%), palpitations (10%)
• Common (1% to 10%): Tachycardia
• Frequency not reported: Hypertensive crisis^[Ref]

Musculoskeletal

• Very common (10% or more): Myalgia (19%), back pain (18%), arthralgia (13%)^[Ref]

Genitourinary

• Very common (10% or more): Urinary tract infection (13%)^[Ref]

Ocular

• Common (1% to 10%): Conjunctivitis^[Ref]

Renal

• Common (1% to 10%): Increased blood creatinine^[Ref]

Oncologic

• Uncommon (0.1% to 1%): Myelodysplastic Syndrome/Acute Myeloid Leukemia^[Ref]

See also:

Further information

Niraparib side effects can vary depending on the individual. Always consult your healthcare provider to ensure the information displayed on this page applies to your personal circumstances.

Note: Medication side effects may be underreported. If you are experiencing side effects that are not listed, submit a report to the FDA by following this guide.

Medical Disclaimer