Which hematologic change can occur with lithium therapy?

• A. Leukopenia
• B. Leukocytosis
• C. Anemia
• D. Thrombocytopenia

Answer: (B)

Leukocytosis is a recognized hematologic effect of lithium therapy. Lithium commonly increases white blood cell counts, particularly neutrophils, due to stimulation of granulopoiesis in the bone marrow. This is thought to involve increased production of growth factors like G-CSF, leading to a mild to moderate rise in WBCs that can occur even in the absence of infection. Because of this, lithium can sometimes be used to treat neutropenia when appropriate. In contrast, leukopenia, anemia, and thrombocytopenia are not typical effects of lithium; they represent decreases in white cells, red cells, or platelets, which are not characteristic of lithium’s action.