Can azathioprine cause anemia (low hemoglobin)? | Rounds Can azathioprine cause anemia (low hemoglobin)? | Rounds
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Can azathioprine cause anemia (low hemoglobin)?

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Azathioprine-Associated Anemia

Azathioprine can cause anemia by causing bone marrow suppression (myelosuppression), which may present as anemia, macrocytosis, and/or pancytopenia. [1][2]

Mechanism of Anemia

Azathioprine toxicity can decrease blood cell production in the bone marrow, which can reduce hemoglobin. [1][2]

Clinical Spectrum of Hematologic Effects

Severe anemia may occur as part of broader cytopenias including leukopenia and thrombocytopenia. [1][3]

Incidence and Risk Context

Hematologic adverse effects including anemias (including macrocytic anemia) and/or pancytopenia are recognized risks in patients treated with azathioprine. [1][3]

Monitoring and When to Seek Urgent Assessment

Complete blood counts (including platelet counts) are recommended for monitoring during azathioprine therapy, because bone marrow depression can occur. [1][4]

Bone marrow depression can require dose reduction or temporary withdrawal when there is a rapid fall in blood counts or persistent cytopenias. [1]

Suggested Evaluation of New or Worsening Anemia on Azathioprine

New anemia during azathioprine treatment should prompt evaluation for azathioprine-induced cytopenia with repeat CBC and medication review, including assessment for concomitant causes of anemia. [1][2]

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