Desferal Dosage

2.1 Recommended Dosage for Treatment of Acute Iron Intoxication for Adults and Pediatric Patients

Intramuscular Administration

Use for all patients not in shock.

The initial recommended dose of Desferal is 1,000 mg intramuscularly once. If needed based on the clinical response, administer subsequent doses of 500 mg every 4 hours to 12 hours. The maximum recommended daily dose is 6,000 mg in 24 hours.

Intravenous Administration

Administer Desferal intravenously to patients in a state of cardiovascular collapse and then only by slow infusion. As soon as the clinical condition of the patient permits, intravenous administration should be discontinued, and the drug should be administered intramuscularly.

The initial recommended IV dose of Desferal is 1,000 mg administered at an infusion rate of up to 15 mg/kg/hr. If needed based on the clinical response administer additional doses of 500 mg over 4 hours to 12 hours at a slower infusion rate of up to 125 mg/hr. The maximum recommended daily dose is 6,000 mg in 24 hours.

2.2 Recommended Dosage for Treatment of Chronic Iron Overload for Adults and Pediatric Patients

Subcutaneous Infusion Administration

The average daily dose of Desferal is usually between 20 and 60 mg/kg. In general patients with serum ferritin level below 2,000 ng/mL require about 25 mg/kg/day. Patients with serum ferritin level between 2,000 and 3,000 ng/mL require about 35 mg/kg/day. Patients with higher serum ferritin may require up to 55 mg/kg/day. It is not advisable to regularly exceed an average daily dose of 50 mg/kg/day except when very intensive chelation is needed in patients who have completed growth. If ferritin levels fall below 1,000 ng/mL, the risk of Desferal toxicity increases; it is important to monitor these patients particularly carefully and perhaps to consider lowering the total weekly dose. The doses specified here are the average daily doses. Since most patients use Desferal less than 7 days a week, the actual dose per infusion usually differs from the average daily dose; e.g., if an average daily dose of 40 mg/kg/day is required and the patient wears the pump 5 nights a week, each infusion should contain 56 mg/kg.

Slow subcutaneous infusion using a portable, light-weight infusion pump over a period of 8 to 12 hours is regarded as effective and especially convenient for ambulatory patients but may also be given over a 24-hour period. Desferal should normally be used with the pump 5 to 7 times a week. Desferal is not formulated to support subcutaneous bolus injection.

Intravenous Administration

Desferal can be administered intravenously if needed in patients with intravenous access.

The recommended dose of Desferal in adults is 40 mg/kg/day to 50 mg/kg/day over 8 hours to 12 hours at a rate of up to 15 mg/kg/hour for 5 days to 7 days per week. Maximum dose is 60 mg/kg/day.

The recommended dose of Desferal in pediatric patients is 20 mg/kg/day to 40 mg/kg/day over 8 hours to 12 hours for 5 days to 7 days per week. The maximum recommended daily dose is 40 mg/kg/day until growth (body weight and linear growth) has ceased.

In case of missed doses, Desferal may be administered prior to or following same day blood transfusion (for example, 1 gram over 4 hours on the day of transfusion); however, the contribution of this mode of administration to iron balance is limited. Desferal should not be administered concurrently with the blood transfusion as this can lead to errors in interpreting side effects such as rash, anaphylaxis and hypotension.

Intramuscular Administration

If given intramuscularly, the recommended dose of Desferal is 500 mg to 1,000 mg per day. The maximum recommended daily dose is 1,000 mg per day.

2.3 Preparation

Reconstitute Desferal prior to administration. Desferal should be further diluted for intravenous infusion. Use appropriate aseptic technique.

Reconstitute each vial of Desferal with Sterile Water for Injection, USP per Table 1. Parenteral drug products should be inspected visually for particulate matter and discoloration prior to administration, whenever solution and container permit. Do not use if visibly opaque particles, discoloration or foreign particles are observed. The reconstituted Desferal solution is an isotonic, clear and colorless to slightly-yellowish solution. Discard unused portion.

If not used immediately, store at room temperature between 20°C to 25°C (68°F to 77°F), excursions permitted between 15°C and 30°C (59°F and 86°F), for a maximum period of 24 hours. Do not refrigerate reconstituted solution.

2.4 Management of Vitamin C Deficiency

Patients with iron overload usually become vitamin C deficient, probably because iron oxidizes the vitamin. As an adjuvant to iron chelation therapy, vitamin C in doses up to 200 mg for adults may be given in divided doses, starting after an initial month of regular treatment with Desferal [see Warnings and Precautions (5.7)]. Vitamin C increases availability of iron for chelation. In general, 50 mg daily suffices for pediatric patients under 10 years old and 100 mg daily for older pediatric patients. Larger doses of vitamin C fail to produce any additional increase in excretion of iron complex.