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Onureg Side Effects

Generic name: azacitidine

Medically reviewed by Last updated on Apr 8, 2024.

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

Applies to azacitidine: oral tablet. Other dosage forms:

Serious side effects of Onureg

Along with its needed effects, azacitidine (the active ingredient contained in Onureg) 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 azacitidine:

More common

Other side effects of Onureg

Some side effects of azacitidine 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

For Healthcare Professionals

Applies to azacitidine: injectable powder for injection, oral tablet, subcutaneous powder for injection.


Very common (10% or more): Nausea (71%), vomiting (54%), constipation (50%), diarrhea (36%), abdominal pain (13%), abdominal tenderness (12%), ascites (11%), leucopenia (10.6%)

Common (1% to 10%): Gingival bleeding, loose stools, mouth hemorrhage, stomatitis, dyspepsia, diverticulitis, oral fungal infection, gastrointestinal hemorrhage, hemorrhoidal hemorrhage

Frequency not reported: Melena, perirectal abscess[Ref]

-Abdominal pain include abdominal pain, abdominal pain upper, abdominal discomfort, and gastrointestinal pain.[Ref]


Very common (10% or more): Thrombocytopenia (70%), anemia (70%), neutropenia (66%), leukopenia (48%), febrile neutropenia (16%)

Common (1% to 10%): Aggravated anemia, hematoma, neutropenic sepsis, pancytopenia splenomegaly, bone marrow failure

Frequency not reported: Agranulocytosis[Ref]


Very common (10% or more): Pyrexia (52%), fatigue (24%), chest pain (16%), asthenia (16%), peripheral edema (13%), transfusion reaction (12%)

Common (1% to 10%): Malaise, chills, post-procedural hemorrhage, sepsis, herpes simplex

Frequency not reported: General physical health deterioration, bacterial infection, blastomycosis, Klebsiella sepsis, septic shock, Staphylococcal bacteremia, Staphylococcal infection, toxoplasmosis

Postmarketing reports: Differentiation syndrome[Ref]


Very common (10% or more): Injection site erythema (43%), injection site reaction (29%), injection site pain (23%), injection site bruising (14%)

Common (1% to 10%): Injection site pruritus, injection site granuloma, injection site pigmentation changes, injection site swelling, injection site induration, injection site hematoma, injection site rash, injection site inflammation, injection site discoloration, injection site nodule, injection site hemorrhage, injection site malaise

Frequency not reported: Catheter site hemorrhage

Postmarketing reports: Injection site necrosis[Ref]


Very common (10% or more): Ecchymosis (31%), petechiae (24%), erythema (17%), rash (14%), pruritus (12%)

Common (1% to 10%): Dry skin, urticaria, skin nodule, cellulitis, skin infection, purpura, alopecia, erythema, macular rash

Uncommon (0.1% to 1%): Sweet's syndrome, pyoderma gangrenosum

Frequency not reported: Pruritic rash, skin induration[Ref]


-Pneumonia include pneumonia, bronchopulmonary aspergillosis, lung infection, Pneumocystis jirovecii pneumonia, atypical pneumonia, pneumonia bacterial, and pneumonia fungal.

-Respiratory tract infection include upper respiratory tract infection, respiratory tract infection, and respiratory tract infection viral.[Ref]

Very common (10% or more): Dyspnea (29%), cough (19%), nasopharyngitis (15%), epistaxis (17%), upper respiratory tract infection (13%), pneumonia (11%)

Common (1% to 10%): Rhinitis, bronchitis, influenza. pharyngolaryngeal pain, exertional dyspnea, sinusitis, pharyngitis, pleural effusion

Rare (less than 0.1%): Interstitial lung disease

Frequency not reported: Hemoptysis, lung infiltration, pneumonitis, respiratory distress, streptococcal pharyngitis, Klebsiella pneumonia[Ref]


Very common (10% or more): Arthralgia (22%), myalgia (16%), musculoskeletal pain (11%), back pain (11.9%), pain in extremity (10.6%)

Common (1% to 10%): Muscle spasms

Frequency not reported: Aggravated bone pain, muscle weakness, neck pain, loin pain, abscess limb, chest wall pain

Postmarketing reports: Necrotizing fasciitis[Ref]

Nervous system

Very common (10% or more): Headache (22%), dizziness (19%)

Common (1% to 10%): Intracranial hemorrhage, syncope, somnolence, lethargy

Frequency not reported: Cerebral hemorrhage, convulsions[Ref]


Very common (10% or more): Anorexia (21%), hyperuricemia (17%), decreased appetite (13%)

Common (1% to 10%): Decreased weight, hypokalemia, dehydration, fluid retention

Rare (less than 0.1%): Tumor lysis syndrome[Ref]


Very common (10% or more): Acute myeloid leukemia (14.3%)

Frequency not reported: Leukemia cutis[Ref]


Common (1% to 10%): Hypotension, hypertension, orthostatic hypotension

Frequency not reported: Atrial fibrillation, cardiac failure, congestive cardiac failure, cardio-respiratory arrest, congestive cardiomyopathy

Postmarketing reports: Pericardial effusion, pericarditis[Ref]


Common (1% to 10%): Eye hemorrhage, conjunctival hemorrhage[Ref]


Very common (10% or more): Anxiety (13%), insomnia (11%)

Common (1% to 10%): Confusional state[Ref]


Common (1% to 10%): Renal failure, elevated serum creatinine, hematuria, urinary tract infection

Uncommon (0.1% to 1%): Renal tubular acidosis

Frequency not reported: Renal toxicity[Ref]

-Urinary tract infection include urinary tract infection, urinary tract infection bacterial, Escherichia urinary tract infection, and cystitis.[Ref]


Uncommon (0.1% to 1%): Hepatic failure, hepatic coma

Frequency not reported: Cholecystitis, cholecystectomy, hepatotoxicity[Ref]


Uncommon (0.1% to 1%): Hypersensitivity reactions[Ref]


Frequency not reported: Anaphylactic shock, systemic inflammatory response syndrome[Ref]


Most common adverse reactions (greater than 30%) by subcutaneous route are: nausea, anemia, thrombocytopenia, vomiting, pyrexia, leukopenia, diarrhea, injection site erythema, constipation, neutropenia, and ecchymosis. Most common adverse reactions by IV route also included petechiae, rigors, weakness, and hypokalemia.

Most common adverse reactions (greater than 10%) by oral route included nausea, vomiting, diarrhea, fatigue or asthenia, constipation, pneumonia, abdominal pain, arthralgia, decreased appetite, neutropenia, respiratory tract infection, thrombocytopenia, leucopenia, febrile neutropenia, dizziness, back pain and pain in extremity.[Ref]


1. (2004) "Product Information. Vidaza (azacitidine)." Celgene Corporation

2. Cerner Multum, Inc. "UK Summary of Product Characteristics."

3. Cerner Multum, Inc. "Australian Product Information."

Further information

Always consult your healthcare provider to ensure the information displayed on this page applies to your personal circumstances.

Some side effects may not be reported. You may report them to the FDA.