Approximately 30% of the world is estimated to be anemic. Iron-deficiency anemia is the most common nutritional deficiency and anemia. Females are up to seven times more likely to be affected than males. This chapter describes the following hematologic disorders: iron-deficiency anemia, sickle cell anemia, chemotherapy-induced neutropenia, hemolytic anemia, anemia of chronic disease, macrocytic anemia and thrombocytopenia. It explains the pathophysiology of the hematologic disorders. The chapter also outlines the clinical manifestations associated with the pathophysiology. It discusses guideline-directed therapies for patients with a hematologic condition and categorizes the types of medications that are used to treat hematologic disorders. The chapter also evaluates the options available in the pharmacologic treatment of the hematologic disorders.