Decitabine is a medication primarily used in the treatment of certain types of blood cancers, such as myelodysplastic syndromes and acute myeloid leukemia. It works by inhibiting DNA methylation, which can help restore normal function to genes that are important for cell growth and differentiation. This drug is typically administered through an injection, either intravenously or subcutaneously. Patients receiving decitabine may experience side effects, including low blood cell counts, fatigue, and increased risk of infections. Regular monitoring by healthcare professionals is essential to manage these potential risks effectively.