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For your specific specialty, access information below about the patients you're seeing and how to test for, diagnose, and manage iron deficiency anemia (IDA).


Underlying gastrointestinal (GI) conditions may put patients at risk for IDA

Absorption is impaired in many patients with GI conditions, limiting the efficacy of oral iron therapy11,12

IDA prevalence for various conditions. IDA prevalence for various conditions.

*Study conducted in Italy and included only Italian subjects.

GI bleeding is found in approximately 50% of patients with IDA.25
GI bleeding can be caused by conditions such as6

Peptic Ulcers. Colon Cancer.

CLINICAL CONSIDERATION Some common GI medications reduce stomach acid, such as proton pump inhibitors, antacids,
and H2 blockers, which can interfere with absorption of oral iron.25

Injectafer is the #1 IV iron therapy by volume among gastroenterologists2†

Injectafer is the #1 IV iron therapy by volume among gastroenterologists2†

Condition and patient type27

As a gastroenterologist, your patients with IDA may present with diverse etiologies, including those of which are not known. In fact, patients with IDA of unknown etiology are frequently referred to a gastroenterologist because, in the majority of cases, the condition has a GI origin. Causes of IDA include malabsorption and gastrointestinal causes. Click on both to learn more:




  • Celiac disease
  • Duodenal resection/gastric bypass surgery
  • Inflammatory bowel disease (ileal-jejunal disease and/or anemia of chronic disease)
  • Helicobacter pylori gastritis
  • Autoimmune gastritis




  • Malignancy
  • Upper gastrointestinal blood loss
    • Gastric/duodenal ulcer
    • Variceal bleeding
    • Esophagitis, erosive gastritis
    • Mallory-Weiss syndrome
    • Angiodysplasia, vascular ectasia
    • Dieulafoy lesions
    • Rare: Meckel diverticula, Cameron lesions
  • Lower gastrointestinal blood loss
    • Diverticulosis/diverticulitis
    • Hemorrhoids, anal fissures, rectal ulcers
    • Angiodysplasia
    • Inflammatory bowel disease (IBD)
    • Infectious colitis

A wide variety of inflammatory conditions can elevate hepcidin, hindering oral iron absorption and reducing serum iron levels28

  • Concomitant therapies such as acid suppressants can also impair oral iron absorption

Symptoms and diagnosis25

Patients with mild IDA are most likely asymptomatic and certain patients may present with nonspecific symptoms such as fatigue, pallor, and dyspnea on exertion. Behavioral changes such as pica (the craving and consumption of nonfood items) and restless legs syndrome may also be observed. Patients with GI causes of IDA may experience symptoms such as a change in stool caliber, epigastric pain, and alterations in bowel habits, weight loss, early satiety, and poor appetite.

IDA is diagnosed through several laboratory tests. Since IDA often arises from bleeding gastrointestinal lesions, many of which are malignant, establishment of a firm diagnosis usually obligates an endoscopic evaluation of the lower and upper GI tract. Many practitioners now regard colonoscopy as an essential component of the anemia evaluation. Other tests include:

  • Serum ferritin—this is the single best laboratory test for the diagnosis of iron deficiency
  • The serum transferrin receptors (sTfR) test, similar to serum ferritin, can be used to estimate body iron stores
  • An erythrocyte zinc protoporphyrin assay (ZnPP) is another laboratory screening method used to assess iron status
  • Fecal occult blood testing (FOBT) detects blood loss from the GI tract

As recommended by the American Gastroenterological Association (AGA), patients who have persistent or recurrent IDA after negative esophagogastroduodenoscopy (EGD) and colonoscopy should undergo small-bowel evaluation.

Three of the most common tests used to diagnose IDA are hemoglobin (Hb), ferritin, and TSAT.

See the common laboratory markers used to monitor IDA.

Injectafer restores iron

Injectafer is a 100% dextran-free IV iron indicated for adult IDA patients of various etiologies, and is the only FDA-approved IV iron that delivers up to 1500 mg of iron in 2 administrations, separated by at least 7 days.2,4‡

Take two 750 mg doses of Injectafer 7 days apart for a total course up to 1500 mg. IV infussion over at least 15 minutes or slow IV push over 7.5 minutes Take two 750 mg doses of Injectafer 7 days apart for a total course up to 1500 mg. IV infussion over at least 15 minutes or slow IV push over 7.5 minutes
Injectafer treatment may be repeated if iron deficiency anemia reoccurs. Monitor serum phosphate levels in patients at risk for low serum phosphate who require a repeat course of treatment (see Important Safety Information).

In Injectafer clinical trials, serious anaphylactic/anaphylactoid reactions were reported in 0.1% (2/1775) of subjects receiving Injectafer.4

§ For adult patients weighing less than 50 kg (110 lb), give each dose as 15 mg/kg body weight for a total cumulative dose not to exceed 1500 mg of iron per course of treatment.

||When administered via IV infusion, dilute up to 750 mg of iron in no more than 250 mL of sterile 0.9% sodium chloride injection, USP, such that the concentration of the infusion is not <2 mg of iron per mL and administer over at least 15 minutes. When administered as a slow IV push, give at the rate of approximately 100 mg (2 mL) per minute.

Injectafer is not indicated to treat the symptoms of IDA.

Intravenous iron is an effective treatment of iron deficiency anemia and should be considered when oral iron is inadequate or cannot be tolerated. The efficacy of oral iron is limited in certain gastrointestinal conditions, such as inflammatory bowel disease, celiac disease, and autoimmune gastritis.27

Adult patients may fail oral iron for a number of reasons, and IDA patients in Injectafer clinical trials were found to have iron deficits of approximately
1500 mg.

  • Data reveals that the adherence rate for oral iron therapy is 40%-60%30
    • Adherence may be affected by side effects25

Calculated iron deficit based on the modified Ganzoni formula: Subject weight in kg x (15 - current hemoglobin g/dL) x 2.4 + 500. If subject TSAT >20% and ferritin >50 ng/mL, the 500-mg constant is not needed.

Choosing Injectafer: VIDEO LIBRARY

Choosing Injectafer: VIDEO LIBRARY

Important Safety Information


Injectafer® (ferric carboxymaltose injection) is indicated for the treatment of iron deficiency anemia (IDA) in adult patients who have intolerance to oral iron or have had unsatisfactory response to oral iron, or who have non-dialysis dependent chronic kidney disease.



Injectafer is contraindicated in patients with hypersensitivity to Injectafer or any of its inactive components.


Symptomatic hypophosphatemia requiring clinical intervention has been reported in patients at risk of low serum phosphate in the postmarketing setting. These cases have occurred mostly after repeated exposure to Injectafer in patients with no reported history of renal impairment. Possible risk factors for hypophosphatemia include a history of gastrointestinal disorders associated with malabsorption of fat-soluble vitamins or phosphate, concurrent or prior use of medications that affect proximal renal tubular function, hyperparathyroidism, vitamin D deficiency and malnutrition. In most cases, hypophosphatemia resolved within three months.

Monitor serum phosphate levels in patients at risk for low serum phosphate who require a repeat course of treatment.

Serious hypersensitivity reactions, including anaphylactic-type reactions, some of which have been life-threatening and fatal, have been reported in patients receiving Injectafer. Patients may present with shock, clinically significant hypotension, loss of consciousness, and/or collapse. Monitor patients for signs and symptoms of hypersensitivity during and after Injectafer administration for at least 30 minutes and until clinically stable following completion of the infusion. Only administer Injectafer when personnel and therapies are immediately available for the treatment of serious hypersensitivity reactions. In clinical trials, serious anaphylactic/anaphylactoid reactions were reported in 0.1% (2/1775) of subjects receiving Injectafer. Other serious or severe adverse reactions potentially associated with hypersensitivity which included, but were not limited to, pruritus, rash, urticaria, wheezing, or hypotension were reported in 1.5% (26/1775) of these subjects

In clinical studies, hypertension was reported in 4% (67/1775) of subjects in clinical trials 1 and 2. Transient elevations in systolic blood pressure, sometimes occurring with facial flushing, dizziness, or nausea were observed in 6% (106/1775) of subjects in these two clinical trials. These elevations generally occurred immediately after dosing and resolved within 30 minutes. Monitor patients for signs and symptoms of hypertension following each Injectafer administration.

In the 24 hours following administration of Injectafer, laboratory assays may overestimate serum iron and transferrin bound iron by also measuring the iron in Injectafer.


In two randomized clinical studies [Studies 1 and 2], a total of 1775 patients were exposed to Injectafer, 15 mg/kg of body weight, up to a maximum single dose of 750 mg of iron on two occasions, separated by at least 7 days, up to a cumulative dose of 1500 mg of iron. Adverse reactions reported by ≥2% of Injectafer-treated patients were nausea (7.2%); hypertension (4%); flushing (4%); injection site reactions (3%); erythema (3%); hypophosphatemia (2.1%); dizziness (2.1%); and vomiting (2%).

The following adverse reactions have been identified during post approval use of Injectafer. Because these reactions are reported voluntarily from a population of uncertain size, it is not always possible to reliably estimate their frequency or establish a causal relationship to drug exposure.

The following adverse reactions have been reported from the post-marketing spontaneous reports with Injectafer: cardiac disorders: tachycardia; general disorders and administration site conditions: chest discomfort, chills, pyrexia; metabolism and nutrition disorders: hypophosphatemia; musculoskeletal and connective tissue disorders: arthralgia, back pain, hypophosphatemic osteomalacia (rarely reported event); nervous system disorders: syncope; respiratory, thoracic and mediastinal disorders: dyspnea; skin and subcutaneous tissue disorders: angioedema, erythema, pruritus, urticaria; pregnancy: fetal bradycardia.


Untreated IDA in pregnancy is associated with adverse maternal outcomes such as postpartum anemia. Adverse pregnancy outcomes associated with IDA include increased risk for preterm delivery and low birth weight.

Severe adverse reactions including circulatory failure (severe hypotension, shock including in the context of anaphylactic reaction) may occur in pregnant women with parenteral iron products (such as Injectafer) which may cause fetal bradycardia, especially during the second and third trimester.

You are encouraged to report Adverse Drug Events to American Regent, Inc. at 1-800-734-9236 or to the FDA by visiting or calling 1-800-FDA-1088.

Please see Full Prescribing Information.

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