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Zejula Side Effects

Generic Name: niraparib

Note: This document contains side effect information about niraparib. Some of the dosage forms listed on this page may not apply to the brand name Zejula.

In Summary

Common side effects of Zejula include: anemia, asthenia, constipation, cough, decreased hemoglobin, decreased neutrophils, decreased platelet count, decreased white blood cell count, dizziness, dyspnea, fatigue, headache, hypertension, increased serum alanine aminotransferase, increased serum aspartate aminotransferase, insomnia, mucositis, nasopharyngitis, nausea, neutropenia, palpitations, skin rash, stomatitis, thrombocytopenia, vomiting, decreased appetite, dysgeusia, and xerostomia. Other side effects include: hypertensive crisis. See below for a comprehensive list of adverse effects.

For the Consumer

Applies to niraparib: oral capsule

Along with its needed effects, niraparib (the active ingredient contained in Zejula) 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:

More common
  • Black, tarry stools
  • bleeding gums
  • blood in the urine or stools
  • blurred vision
  • chills
  • cough
  • dizziness
  • fast, irregular, pounding, or racing heartbeat or pulse
  • fever
  • headache
  • lower back or side pain
  • nervousness
  • painful or difficult urination
  • pale skin
  • pinpoint red spots on the skin
  • pounding in the ears
  • slow or fast heartbeat
  • sore throat
  • troubled breathing with exertion
  • ulcers, sores, or white spots in the mouth
  • unusual bleeding or bruising
  • unusual tiredness or weakness
Less common
  • Chest pain
  • swollen glands

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:

More common
  • Acid or sour stomach
  • back pain
  • belching
  • bladder pain
  • bloody or cloudy urine
  • change in taste
  • cracked lips
  • decreased appetite
  • diarrhea
  • difficulty having a bowel movement (stool)
  • difficulty with swallowing
  • dry mouth
  • fear or nervousness
  • frequent urge to urinate
  • heartburn
  • indigestion
  • lack or loss of strength
  • loss of taste
  • lower back or side pain
  • nausea
  • stomach discomfort, upset, or pain
  • trouble sleeping
  • vomiting

For Healthcare Professionals

Applies to niraparib: oral capsule


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]


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]


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]


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


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]


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]


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


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


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


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


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


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


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


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


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


1. "Product Information. Zejula (niraparib)." Tesaro Inc., Waltham, MA.

Some side effects of Zejula may not be reported. Always consult your doctor or healthcare specialist for medical advice. You may also report side effects to the FDA.

Disclaimer: Every effort has been made to ensure that the information provided is accurate, up-to-date and complete, but no guarantee is made to that effect. In addition, the drug information contained herein may be time sensitive and should not be utilized as a reference resource beyond the date hereof. This material does not endorse drugs, diagnose patients, or recommend therapy. This information is a reference resource designed as supplement to, and not a substitute for, the expertise, skill , knowledge, and judgement of healthcare practitioners in patient care. The absence of a warning for a given drug or combination thereof in no way should be construed to indicate safety, effectiveness, or appropriateness for any given patient. does not assume any responsibility for any aspect of healthcare administered with the aid of materials provided. The information contained herein is not intended to cover all possible uses, directions, precautions, warnings, drug interactions, allergic reactions, or adverse effects. If you have questions about the substances you are taking, check with your doctor, nurse, or pharmacist.