IRON DEXTRAN Drug Interactions: What You Need to Know

INTERACTIONS

7.1 Drug/Laboratory Test Interactions Drug interactions involving INFeD have not been studied. Concomitant use of angiotensin-converting enzyme inhibitor drugs may increase the risk for anaphylactic-type reactions to an iron dextran product. Large doses of iron dextran (5 mL or more) have been reported to give a brown color to serum from a blood sample drawn 4 hours after administration. INFeD may cause falsely elevated values of serum bilirubin and falsely decreased values of serum calcium. Serum iron determinations (especially by colorimetric assays) may not be meaningful for 3 weeks following the administration of INFeD. Examination of the bone marrow for iron stores may not be meaningful for prolonged periods following iron dextran therapy because residual iron dextran may remain in the reticuloendothelial cells. Bone scans involving 99m Tc-diphosphonate have been reported to show a dense, crescentic area of activity in the buttocks, following the contour of the iliac crest, 1 to 6 days after intramuscular injections of INFeD. Bone scans with 99m Tc-labeled bone seeking agents, in the presence of high serum ferritin levels or following INFeD infusions, have been reported to show reduction of bony uptake, marked renal activity, and excessive blood pool and soft tissue accumulation.

INFeD is contraindicated in patients who have demonstrated a previous hypersensitivity to iron dextran [see Warnings and Precautions ( 5.1 ) ] . Known hypersensitivity to INFeD ( 4 )

AND PRECAUTIONS Delayed Reactions: May occur with large intravenous doses. ( 5.2 )

Increased

Risk of Toxicity in Patients with Underlying Conditions: Monitor for toxicity in these patients. ( 5.3 )

Iron

Overload: Excessive therapy can lead to iatrogenic hemosiderosis. Do not administer to patients with iron overload. Periodically monitor hematologic and iron parameters. ( 5.4 )

5.1 Hypersensitivity Reactions Serious hypersensitivity reactions, including anaphylactic-type reactions, some of which have been life-threatening and fatal, have been reported following the parenteral administration of iron dextran products, including INFeD. Such reactions have been generally characterized by sudden onset of respiratory difficulty and/or cardiovascular collapse. Fatal reactions have been reported following the test dose of iron dextran and have also occurred in situations where the test dose was tolerated. Administer only in a setting where resuscitation equipment and medications are available. Administer a test dose of INFeD prior to the first therapeutic dose <span class="opacity-50 text-xs">[see Dosage and Administration ( 2.4 ) ]</span>. Observe patients for at least one hour after the test dose before administering the remainder of the initial therapeutic dose. During all INFeD administrations, observe patients for signs or symptoms of anaphylactic-type reactions. Use INFeD only in patients in whom clinical and laboratory investigations have established an iron deficient state not amenable to oral iron therapy. The factors that affect the risk for anaphylactic-type reactions to iron dextran products are not fully known but limited clinical data suggest the risk may be increased among patients with a history of drug allergy or multiple drug allergies. Additionally, concomitant use of angiotensin-converting enzyme inhibitor drugs may increase the risk for reactions to an iron dextran product. The extent of risk for anaphylactic-type reactions following exposure to any specific iron dextran product is unknown and may vary among the products. If hypersensitivity reactions occur during administration, stop INFeD immediately and manage reaction medically.

5.2 Delayed Reactions Large intravenous doses, such as used with total dose infusions (TDI), have been associated with an increased incidence of adverse reactions. The adverse reactions are frequently delayed (1 to 2 days) reactions typified by one or more of the following symptoms: arthralgia, backache, chills, dizziness, moderate to high fever, headache, malaise, myalgia, nausea, and vomiting. The onset is usually 24 to 48 hours after administration and symptoms generally subside within 3 to 4 days. The etiology of these reactions is not known. Do not exceed a total daily dose of 2 mL undiluted INFeD. 5. 3 Increased Risk of Toxicity in Patients with Underlying Conditions Monitor for iron toxicity when INFeD is used in patients with serious impairment of liver function. It should not be used during the acute phase of infectious kidney disease. Adverse reactions experienced following administration of INFeD may exacerbate cardiovascular complications in patients with pre-existing cardiovascular disease. Patients with rheumatoid arthritis may have an acute exacerbation of joint pain and swelling following the administration of INFeD. Patients with a history of significant allergies and/or asthma may have an increased risk of hypersensitivity reactions <span class="opacity-50 text-xs">[see Dosage and Administration ( 5.1 )]</span>. 5. 4 Iron Overload Excessive therapy with parenteral iron can lead to excess storage of iron with the possibility of iatrogenic hemosiderosis. All adult and pediatric patients receiving INFeD require periodic monitoring of hematologic and iron parameters (hemoglobin, hematocrit, serum ferritin and transferrin saturation). Do not administer INFeD to patients with evidence of iron overload.