Hydroxyurea use in sickle cell disease: the battle with low prescription rates, poor patient compliance and fears of toxicities

Background of sickle cell disease Sickle cell disease (SCD) is the most common inherited blood disorder in the USA, affecting approximately 89,000 Americans or one in 400 African–Americans [1]. SCD is caused by inheritance of the sickle b-globin gene, either in homozygous form (HbSS) or in combination with hemoglobin C (HbSC), b-thalassemia (HbSbthal) or several less common hemoglobin genotypes [2]. This disorder of hemoglobin structure manifests as a chronic debilitating disease characterized by chronic and episodic pain, hemolytic anemia, severe infections, stroke and pulmonary complications beginning in infancy and lasting throughout life [2].