Lithium and hematopoiesis: understanding the systemic impact of long-term use

INTRODUCTION Lithium is recognized as a critical therapeutic agent in the management of mood disorders, particularly bipolar disorder, due to its significant mood--stabilizing properties.Its pharmacodynamic actions, including modulation of neurotransmitter activity and inhibition of pathways like glycogen synthase kinase-3, are central to its efficacy.However, lithium's narrow therapeutic window necessitates precise monitoring to avoid systemic toxicity, especially in patients undergoing long-term treatment.Beyond its psychiatric benefits, lithium exerts considerable hematological effects, influencing granulopoiesis, bone marrow function, and the production of white and red blood cells.The introduction emphasizes the need to closely monitor hematological parameters during lithium therapy, particularly in relation to leukocytosis, neutrophilia, platelet dysfunction, and anemia.OBJETIVE To explore and analyze the hematological effects of long-term lithium therapy, particularly its impact on leukocytosis, neutrophilia, platelet function, and red blood cell production, while assessing clinical implications for patients.METHODS This is a narrative review which included studies in the MEDLINE -PubMed (National Library of Medicine, National Institutes of Health), COCHRANE, EMBASE and Google Scholar databases, using as descriptors: "Lithium-induced hematological changes" OR "Mood stabilizers and blood cell alterations" OR "Neutrophilia and leukocytosis in lithium therapy" OR "Platelet dysfunction and lithium therapy" OR "Bone marrow suppression and lithium use" in the last years.RESULTS AND DISCUSSION Lithium therapy is associated with several hematological changes, the most notable being lithium-induced leukocytosis, which is dose-dependent and occurs primarily through increased neutrophil production.This increase in white blood cell count, while often benign, requires close monitoring in factors and clinical profile.