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Desferrioxamine mesylate is poorly absorbed from the gastrointestinal tract. Following parenteral administration, desferrioxamine forms chelates with metal ions and is also metabolised, primarily in the plasma. The iron-desferrioxamine chelate is excreted in the urine and bile. Desferrioxamine is absorbed during peritoneal dialysis if added to the dialysis fluid.
Acute Iron Poisoning : IM inj. for patients not in shock: 1g initially followed by 500mg every 4hrs for two doses. Subsequent doses 500mg 4-12hrly as reqd. upto a max. of 69 in 24hours.
IV infusion for patients with cardiovascular collapse : 15mg/kg/hr max 80mg/kg in 24hrs.
Chronic Iron Overload(Ex:Transfusional Hemosiderosis Esp. In Thalassemia Patients): Daily dose of 0.5-1g IM. Additionally 2g IV infusion given separately with each unit of blood transfused. Diagnostic test for Iron Storage Disease: Inject500mg IM & measure urinary iron in the next 6hrs. Excretion of 1mg iron is suggestive of iron storage disease & more than 1.5mg is pathological.
It is a chelating agent which has a high affinity for ferric iron. When injected, it is forums a stable water-soluble iron-complex (ferrioxamine) which is readily excreated in the urine & in bile. It can also chelate aluminium & thus useful in aluminium overload. Nonetheless, Desferrioxamine is primarily a chelator used in acute iron poisoning & chronic iron overload.
Desferrioxamine is usually administered parenterally and thus drug interactions due to chelation with oral metal ions are not a problem.
On i.v. injection : Flushing, urticaria, hypotension, shock, tachypnoea, hypoxaemia, tachycardia, cardiac arrhythmias, convulsions.
On s.c. or i.m. : Local pain, pruritus, erythema, swelling, GIT disturbances, dysuria, fever, allergic skin rashes. Leg cramps on long term therapy. Reversible ocular and auditory disturbances. Reduction of growth in very young children, thrombocytopenia.
When adminstered over prolonged periods, visual acuity tests, slitlamp examinations, funduscopy and audiometry are recommended periodically. Impaired renal function, children below 3 years. Increased susceptibiliby to infection, particularly for Yersinia species. Concomitant use of ascorbic acid. Severe fungal infections have been reported.
Pregnancy : May be used with caution only if potential benefit outweighs risks to the foetus.
Brest Feeding : Use with caution.
Men : May be used.