For individuals suffering from iron deficiency anemia, the most common treatment is oral iron supplements. However, intravenous iron allows complete replacement of iron and alleviation of anemia in one (or more) sessions. With the development of safer solutions, IV iron has been used more often for anemic individuals with inflammatory bowel disease, gynecological and obstetric issues, renal failure, and cancer. Yet it is still an underutilized method due to outdated methods and safety concerns. IV iron may be particularly helpful for older individuals, who may not even realize that they have iron deficiency.

Anemia indicates that you don’t have enough healthy red blood cells to carry adequate oxygen to your body’s tissues. Iron deficiency is the most common cause of anemia worldwide, affecting approximately 27% of the world’s population. It is more common in developing countries.

It is important to note that iron deficiency can also occur without anemia, and is at least twice as common as anemia. Iron deficiency without anemia refers to low iron stores that do not meet the body’s iron requirements. It has similar symptoms, diagnosis, and treatment options.

Iron deficiency causing anemia may be due to blood loss, menstruation and pregnancy in women and their children, malaria, hookworm, dietary conditions lacking adequate iron, celiac disease, cancer, kidney disease, and conditions causing an inability to absorb iron. About 10% of individuals over 65 years and more than 20% of individuals over 85 years are anemic. Anemia in the elderly is typically mild, but results in  adverse outcomes like longer hospitalization, disability, and increased mortality risk and impacts on quality of life (fatigue, depression, frailty, etc.).

Iron deficiency is extremely common in individuals with chronic inflammation (chronic heart failure, chronic kidney disease, cancers, and bowel inflammatory diseases).

Initially, iron deficiency anemia can be so mild that it goes unnoticed. But as the body becomes more deficient in iron and anemia worsens, the signs and symptoms intensify. Note that iron deficiency without anemia has many of the same symptoms:

Anemia may be identified by the red blood cell count (hematocrit) or hemoglobin level in blood.

To understand if anemia is caused by iron deficiency, serum ferritin (a protein containing iron) is a good test. Ferritin is a simple and inexpensive blood test for iron stores, but doctors may not always prescribe it. You can ask for a ferritin test from your doctor, or order one online through sources such as Ulta Lab Tests or Walk-In-Lab. However, diagnosis of iron deficiency is complicated for individuals with inflammatory diseases such as inflammatory bowel disease because ferritin may appear falsely normal even when iron is actually deficient.

A definitive diagnosis usually considers serum ferritin, percent transferrin saturation (TSAT), and hemoglobin, which correlate best with iron status. The definition of anemia varies according to age, sex, race, and how the blood was collected. An additional complexity is that medical guidelines for testing and interpreting data are not standardized and vary country by country.

Iron supplementation is usually the prescribed treatment for anemia. Iron can be taken via oral iron (tablets or liquid) and as an intravascular infusion. Oral iron frequently causes side effects (such as gastrointestinal problems, headache, cramps) leading to discontinuation and treatment failure in a significant portion of people.

Intravenous iron has many benefits over oral iron. A 2015 meta-analysis reported that oral iron supplement caused 2.6 times the odds of  gastrointestinal side-effects compared to placebo or IV iron in participants who were not pregnant and did not have inflammatory bowel disease. Iron provided via IV also has the significant advantage of rapid replenishment of iron throughout the body. Often in as little as one or two transfusions, iron levels are completely recovered. In a randomized, controlled trial, hemoglobin reached a normal level in 80% of anemic women receiving 1-2 intravenous iron transfusions compared to 51% of women using oral iron.

IV iron is especially useful in people with IBD as it bypasses the gut where iron can actually make the symptoms of IBD worse. It is also useful to treat iron deficiency in women with heavy uterine bleeding, pregnancy, bariatric surgery, restless legs syndrome, and high altitude sickness.

Some doctors may be reluctant to use IV iron because an older high-molecular-weight iron called dextran was associated with severe infusion reactions. However, iron formulations used today are much safer.

Intravenous iron is currently underutilized, and  should be considered especially in iron deficient individuals with chronic inflammatory conditions and when oral therapy is poorly tolerated or ineffective.

If you have been diagnosed with iron deficiency with or without anemia, talk to your doctor about treatment options to see if intravenous iron is right for you. To diagnose an iron deficiency, evaluation of serum ferritin level, hemoglobin level, and percent transferrin saturation can be completed. If your doctor is not familiar with the modern use of intravenous iron to treat iron deficiency, the references under Additional Resources below may be useful. To find an iron infusion center, you can try this locator service from the National Infusion Center Association.