A. To treat Iron intoxication when serum iron is greater than 450-500 mcg/dl, or when there are clinical signs of significant iron intoxication ( e.g shock, acidosis , severe GE )

B. It is used sometimes as a diagnostic test to determine the presence of free iron by observing the characteristic vin rose color in urine , which is not reliable indicator

C. Treatment of aluminum toxicity in patients with renal failure

Dose : IV is the preferred route, as infusion in a dose not to exceed 15mg/kg/hr

Adverse effects:

1- Hypotension or anaphylactoid type reaction

2- Local pain and induration and abscess formation with IM injection

3- Infusion more than 24 hrs is associated with ARDS

References :

1- Olson's Poisoning and drug overdose , 6th edition

Sadaf Sheikh

Aug 14, 2021

Thanks for the post.

Q1. Indication of Desferrioxamine mesilate

- It is a chelating agent for trivalent iron and aluminium ions. Desferrioxamine mesilate takes up iron either free or bound to ferritin and haemosiderin. Since both ferrioxamine and aluminoxamine are completely excreted, desferrioxamine mesilate promotes the excretion of iron and aluminium in urine and faeces thus reducing pathological iron or aluminium deposits in the organs and tissues.

- Iron overload - acute iron poisoning; primary and secondary haemochromatosis including thalassaemia and transfusional haemosiderosis; in patients in whom concomitant disorders (e.g. severe anaemia, hypoproteinaemia, renal or cardiac failure) preclude phlebotomy; and for the diagnosis of iron storage disease and sideroblastic anaemia, auto-immune haemolytic anaemia and other chronic anaemias.

- Aluminium overload - in patients on maintenance dialysis for ESRD where preventative measures (e.g. reverse osmosis) have failed and with proven aluminium-related bone disease and/or anaemia, dialysis encephalopathy; and for diagnosis of aluminium overload.

Q2. Usual dose and associated side effects

Parenteral Desferrioxamine mesilate treatment should be considered in any of the following situations:

• all symptomatic patients exhibiting more than transient minor symptoms (e.g. more than one episode of emesis or passage of one soft stool),

• patients with evidence of lethargy, significant abdominal pain, hypovolaemia, or acidosis,

• patients with positive abdominal radiograph results demonstrating multiple radio-opacities (the great majority of these patients will go on to develop symptomatic iron poisoning),

• any symptomatic patient with a serum iron level greater than 300 to 350 micro g/dL regardless of the total iron binding capacity (TIBC).

The dosage and route of administration should be adapted to the severity of the poisoning.

The recommended rate for infusion is 15 mg/kg per hour and should be reduced as soon as the situation permits, usually after 4 to 6 hours so that the total intravenous dose does not exceed a recommended 80 mg/kg in any 24 hour period.

However, if the option to infuse intravenously is not available and if the intramuscular route is used the normal dosage is 2 g for an adult and 1g for a child, administered as a single intramuscular dose.

If the patient initially developed vin-rose coloured urine with Desferrioxamine mesilate therapy, it seems reasonable that urine colour should return to normal before halting Desferrioxamine mesilate (absence of vin-rose urine is not sufficient by itself to indicate discontinuation of Desferrioxamine mesilate).

The effectiveness of treatment is dependent on an adequate urine output in order that the iron complex (ferrioxamine) is excreted from the body. Therefore if oliguria or anuria develop, peritoneal dialysis or haemodialysis may become necessary to remove ferrioxamine.

Theoretically 100 mg Desferrioxamine mesilate can chelate 8.5 mg of ferric iron.

Desferrioxamine mesilate therapy should be commenced after the first 10- 20 blood transfusions, or when there is evidence from clinical monitoring that chronic iron overload is present (e.g. serum ferritin >1000 nanogram/mL.

Adverse effects: list is exhausting but worth mentioning are:

1. It may increase the susceptibility for fungal infections (and other infections such as Yersinia) and lead to growth failure, allergic reactions, ophthalmic toxicity, or ototoxicity.

2. Disturbances of vision and hearing have been reported during prolonged therapy.

3. ARDS has been described following treatment with excessively high IV doses of desferrioxamine in patients with acute iron intoxication, and also in thalassaemic patients.