Secondary Iron Overload
(See also Overview of Iron Overload.)
Secondary iron overload occurs when iron accumulates in the body because people take too many iron supplements, receive a large number of blood transfusions, or have a disorder in which they cannot form red blood cells efficiently.
Severe complications are less likely than in people who have hemochromatosis, a genetic disorder that causes iron overload. However, some people develop complications involving the heart, the liver, and endocrine organs.
Secondary iron overload typically occurs in people who have disorders that impair red blood cell production such as
In such disorders, the body sometimes increases the amount of iron it absorbs. However, the body cannot always use all of the iron because of the difficulty of producing new red blood cells. In such cases, iron overload can occur.
Iron also can accumulate in the body when people take in too much iron from
Iron therapy given in excessive amounts or for too long
Repeated blood transfusions
Men and postmenopausal women do not usually need to take iron supplements. If they do take supplements, they may have excess iron in the body, although usually not enough to be dangerous.
People with mild iron overload usually have no symptoms. Others typically feel weak and fatigued. Severe iron overload causes the same symptoms as in hemochromatosis:
The goal of treatment is to reduce the body's iron content. For some people, treatment is to remove blood (phlebotomy). However, many people with secondary iron overload also have anemia. Because phlebotomy worsens anemia, these people are given iron chelation therapy.
Iron chelation may be given by mouth using deferasirox or deferiprone or by an infusion of deferoxamine, which can be given under the skin (subcutaneous) or into a vein (intravenous).
Iron chelation drugs given by mouth are very effective in lowering the iron level in the body. Side effects of oral iron chelation include abdominal pain, diarrhea, and rash. The treatment sometimes causes liver and kidney damage, so blood tests are done periodically to monitor the function of these organs.
Deferoxamine infusion for iron chelation is usually given overnight. Side effects include digestive upset, low blood pressure, and severe allergic reaction (anaphylaxis). Sometimes people have hearing and vision loss with long-term use.