Sickle cell anemia is a pathophysiological condition in which the patient’s red blood cells change their shape from normal biconvex to sickle-shaped. The change in the form of the cells is caused by damage to the synthesis of hemoglobin, which is the oxygen carrier in the bloodstream. As a result of gene mutations, hemoglobin changes its shape, which leads to a change in the form of red blood cells. Patients with sickle cell anemia are pale and anemic and are also at risk for thrombosis. Modern medicine offers drug treatment for this condition, and future therapy will probably diagnose the disease genetically before the fetus is born.