Hemoglobinemia (British Haemoglobinaemia) is a medical condition in which there is an excess of hemoglobin in the blood plasma. This is an effect of intravascularhemolysis, in which hemoglobin separates from red blood cells, a form of anemia. Hemoglobinemia can be caused by intrinisic or extrinsic factors. When hemoglobinemia is internally caused, it is a result of recessive genetic defects that cause the red blood cells to lyse, letting the hemoglobin spill out of the cell into the blood plasma. In externally caused hemoglobinemia, an outside attacker acts as an antibody against the red blood cells. This can cause the cells to be destroyed and their hemoglobin released.