IRON DEXTRAN

Chemistry - Iron dextran is a complex of ferric oxyhydroxide and low molecular weight partially hydrolyzed dextran derivative. The commercially available injection occurs as a dark brown, slightly viscous liquid that is completely miscible with water or normal saline and has a pH of 5.2 - 6.5.

Storage, Stability, Compatibility

Iron dextran injection should be stored at room temperature (15-30°C); avoid freezing. Iron dextran injection is reportedly incompatible with oxytetracycline HCl and sulfadiazine sodium.

Pharmacology - IRON DEXTRAN

Iron is necessary for myoglobin and hemoglobin in the transport and utilization of oxygen. While neither stimulating erythropoiesis nor correcting hemoglobin abnormalities not caused by iron deficiency, iron administration does correct both physical symptoms and decreased hemoglobin levels secondary to iron deficiency.
Ionized iron is also a component in the enzymes cytochrome oxidase, succinic dehydrogenase, and xanthine oxidase.
Uses, Indications - Iron dextran is used in the treatment and prophylaxis of iron deficiency anemias, primarily in neonatal food-producing animals.

Pharmacokinetics - IRON DEXTRAN

After IM injection, iron dextran is slowly absorbed primarily via the lymphatic system. About 60% of the drug is absorbed within 3 days of injection and up to 90% of the dose is absorbed after 1-3 weeks. The remaining drug may be absorbed slowly over several months.
After absorption, the reticuloendothelial cells of the liver, spleen and bone marrow gradually clearthe drug from the plasma. The iron is cleaved from the dextran component and the dextran is thenmetabolized or excreted. The iron is immediately bound to protein elements to form eitherhemosiderin, ferritin or transferrin. Iron crosses the placenta, but in what form is unknown. Onlytraces of iron are excreted in milk.
Iron is not readily eliminated from the body. Iron liberated by the destruction of hemoglobin isreused by the body and only small amounts are lost by the body via hair and nail growth, normalskin desquamation and GI tract sloughing. Accumulation can result with repeated dosing as onlytrace amounts of iron are eliminated in the feces, bile or urine.

Contraindications, Precautions, Reproductive Safety

Iron dextran is contraindicated in patients with known hypersensitivity to it, or with any anemia other than iron deficiency anemia. It isalso not to be used in patients with acute renal infections, and should not be used in conjunctionwith oral iron supplements.
High dosages may cause increased incidences of teratogenicity and embryotoxicity. Use onlywhen clearly necessary at recommended doses in pregnant animals.

Adverse Effects, Warnings

The manufacturers of iron dextran injection for use in pigs state thatoccasionally pigs may react after injection with iron dextran, characterized by prostration andmuscular weakness. Rarely, death may result as a result of an anaphylactoid reaction. Iron dextranused in pigs born of vitamin E/selenium-deficient sows may demonstrate nausea, vomiting andsudden death within 1 hour of injection. Iron dextran injected IM in pigs after 4 weeks of age maycause muscle tissue staining.
Large SQ doses have been associated with the development of sarcomas in laboratory animals(rabbits, mice, rats, and hamsters).

Overdosage, Acute Toxicity

Depending on the size of the dose, inadvertent overdose injectionsmay require chelation therapy. For more information, refer to the Ferrous Sulfate monograph forinformation on using deferoxamine and other treatments for iron toxicity.

Drug Interactions

Because chloramphenicol may delay the response to iron administration, avoid using chloramphenicol in patients with iron deficiency anemia.
Drug/Laboratory Interactions - Large doses of injectable iron may discolor the serum brownwhich can cause falsely elevated serum bilirubin values and falsely decreased serum calciumvalues. After large doses of iron dextran, serum iron values may not be meaningful for up to 3weeks.