In our hematology-oncology clinic, we treat many patients with chronic pain and anemia from sickle cell disease. The abnormalities in the red cells of patients with sickle cell disease causes hemoglobin to deoxygenate and polymerize, leading to red cell destruction. Voxelotor is a inhibitor of the hemoglobin S polymerization. Once daily oral dosing of voxelotor was shown in a randomized trial to increase hemoglobin levels and reduce markers of hemolysis (red cell destruction). This has been show to improve anemia but has not been studied as to whether it will decrease frequency of sickle crises. Voxelotor has now been approved by the FDA for patients with sickle cell disease.