This is very important because iron 2+ can move more easily around the body than iron 3+, and is also the form of iron that most easily binds to chelators such as DFO. For this reason iron 2+ - the ferrous form - is often called the "chelatable" iron, while iron 3+ - the ferric form - is the immobile iron found in storage compartments of the body such as the liver, bound to carrier proteins such as ferritin and haemosiderin. One way to increase the amount of iron released by these proteins is by administering vitamin C supplements along with DFO. Experts advise that patients with thalassaemia should take vitamin C every day, ideally at the same time as DFO is administered. However, it is generally recommended that patients only begin taking vitamin C supplements after they have been receiving DFO for a few weeks. Recommended daily doses of vitamin C are 50mg for children <10 years of age and 100mg for older children. Doses should not exceed 200mg/day. Patients whose diet regularly includes oranges or fresh juice may not need additional vitamin C supplements: one large orange, for example, contains 75mg of vitamin C, while 100ml of fresh orange juice contains 50mg of vitamin C. As with all medicines and supplements, doses should only be adjusted in consultation with a doctor. It is important to note that too much vitamin C can have a toxic effect on patients, mobilising too much iron. Vitamin C supplements may therefore be particularly harmful to patients who are not receiving DFO, as iron mobilised by the vitamin C will remain unbound, causing tissue damage.
When to start iron chelation treatment Patients with thalssaemia major should only begin DFO treatment once they have begun regular blood transfusion therapy. DFO does not solve any of the problems caused by insufficient blood transfusion therapy, such as anaemia, bone changes or enlargement of the liver and spleen. DFO should not be given to untransfused or under-transfused patients unless they are over 10 years old or there is evidence of iron-loading. As a general rule, patients should begin iron chelation treatment once they have had 10-20 transfusions, or when ferritin levels rise above 1000Ă&#x152;g/l.
How to prepare, store and use desferrioxamine It took more than 30 years of clinical experience for
42