Iron deficiency anemia medical therapy
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Editor-In-Chief: C. Michael Gibson, M.S., M.D. [1]
Overview
Medical Therapy
Before any treatment is commenced there should be definitive diagnosis of the underlying cause for iron deficiency, particularly in older patients who are most susceptible to colorectal cancer and the gastrointestinal bleeding it often causes. In adults, 60% of patients with iron deficiency anemia may have underlying gastrointestinal disorders leading to chronic blood loss.[1]
It is likely that the cause of the iron deficiency will need treatment as well.
If the cause is dietary iron deficiency, iron supplements, usually with iron (II) sulfate, ferrous gluconate, or iron amino acid chelate NaFeEDTA, will usually correct the anemia.
Recent research suggests the replacement dose of iron, at least in the elderly with iron deficiency, may be as little as 15 mg per day of elemental iron [2].
There can be a great difference between iron intake and iron absorption, also known as bioavailability. Scientific studies indicate iron absorption problems when iron is taken in conjunction with milk, tea, coffee and other substances. There are already a number of proven solutions for this problem, including:
- Fortification with ascorbic acid, which increases bioavailability in both presence and absence of inhibiting substances, but which is subject to deterioration from moisture or heat. Ascorbic acid fortification is usually limited to sealed dried foods, but individuals can easily take ascorbic acid with basic iron supplement for the same benefits.
- Microencapsulation with lecithin, which binds and protects the iron particles from the action of inhibiting substances. The primary benefit over ascorbic acid is durability and shelf life, particularly for products like milk which undergo heat treatment.
- Using an iron amino acid chelate, such as NaFeEDTA, which similarly binds and protects the iron particles. A study performed by the Hematology Unit of the University of Chile indicates that chelated iron (ferrous bis-glycine chelate) can work with ascorbic acid to achieve even higher absorption levels [3].
- Separating intake of iron and inhibiting substances by a couple of hours.
- Using goats milk instead of cows milk.
- Gluten-free diet resolves some instances of iron-deficiency anemia.
Iron bioavailability comparisons require stringent controls, because the largest factor affecting bioavailability is the subject's existing iron levels. Informal studies on bioavailability usually do not take this factor into account, so exaggerated claims from health supplement companies based on this sort of evidence should be ignored. Scientific studies are still in progress to determine which approaches yield the best results and the lowest costs.
If anemia does not respond to oral treatments, it may be necessary to administer iron parenterally (e.g., as iron dextran) using a drip or haemodialysis. Parenteral iron involves risks of fever, chills, backache, myalgia, dizziness, syncope, rash, anaphylactic shock[4] and secondary iron overload. Epinephrine is used to counter anaphylactic shock, and Chelation therapy is used to manage secondary iron overload [5].
A follow up blood test is essential to demonstrate whether the treatment has been effective.
Note that iron supplements must be kept out of the reach of children, as iron-containing supplements are a frequent cause of poisoning in the pediatric age group.
"Iron supplementation should be considered for women with unexplained fatigue who have ferritin levels below 50 μg/L". [6] In this trial, the average mean corpuscular volume was normal.
Food sources of Iron
Iron deficiency can have serious health consequences that diet may not be able to quickly correct, and iron supplementation is often necessary if the iron deficiency has become symptomatic. However, mild iron deficiency can be corrected, and prevented, by eating iron-rich foods. Because iron is an absolute requirement for most of the earth's plants and animals, a wide range of food can provide iron. However, these foods are absorbed and processed differently by the body; for instance, iron from meat (heme iron source) is more easily broken down and absorbed than iron in grains (nonheme iron source), and minerals and chemicals in one type of food may inhibit absorption of iron from another type of food eaten at the same time.[2] Because iron from plant sources is less easily absorbed than the heme-bound iron of animal sources, vegetarians and vegans should have a somewhat higher total daily iron intake than those who eat meat, fish or poultry.[3] Legumes and dark-green leafy vegetables like broccoli, kale and oriental greens are especially good sources of iron for vegetarians and vegans. However, spinach and swiss chard contain oxalates which bind iron making it largely unavailable for absorption. Iron from nonheme sources is more readily absorbed if consumed with foods that contain either heme-bound iron or vitamin C.
| Food | Serving size |
Miligrams per serving |
% DV* |
|---|---|---|---|
| Chicken liver (cooked) | 3˝ ounces | 12.8 | 70 |
| Oysters(breaded and fried) | 6 pieces | 4.5 | 25 |
| Beef, chuck (lean, braised) | 3 ounces | 3.2 | 20 |
| Clams (breaded, fried) | 1 cup | 3.0 | 15 |
| Beef tenderloin (roasted) | 3 ounces | 3.0 | 15 |
| Turkey ( dark meat, roasted) | 3˝ ounces | 2.3 | 10 |
| Beef, eye of round (roasted) | 3 ounces | 2.2 | 10 |
| Turkey, light meat (roasted) | 3˝ ounces | 1.6 | 8 |
| Chicken, leg, meat only (roasted) | 3˝ ounces | 1.3 | 6 |
| Tuna, fresh bluefin (cooked) | 3 ounces | 1.1 | 6 |
| Chicken breast (roasted) | 3 ounces | 1.1 | 6 |
| Halibut (cooked) | 3 ounces | 0.9 | 6 |
| Blue crab (cooked) | 3 ounces | 0.8 | 4 |
| Pork loin (broiled) | 3 ounces | 0.8 | 4 |
| Tuna white (canned in water) | 3 ounces | 0.8 | 4 |
| Shrimp (mixed species, cooked) | 4 large | 0.7 | 4 |
| Food | Serving size |
Miligrams per serving |
% DV* |
|---|---|---|---|
| Ready-to-eat cereal (100% iron fortified | cup | 18.0 | 100 |
| Oatmeal, instant, fortified (prepared with water | 1 cup | 10.0 | 60 |
| Soybeans, mature (boiled) | 1 cup | 8.8 | 50 |
| Lentils (boiled) | 1 cup | 6.6 | 35 |
| Kidney beans mature (boiled) | 1 cup | 5.2 | 25 |
| Lima beans large, mature (boiled) | 1 cup | 4.5 | 25 |
| Navy beans mature (boiled) | 1 cup | 4.5 | 25 |
| Ready-to-eat cereal (25% iron fortified) | 1 cup | 4.5 | 25 |
| Black beans mature (boiled) | 1 cup | 3.6 | 20 |
| Pinto beans mature (boiled) | 1 cup | 3.6 | 20 |
| Molasses (blackstrap) | 1 tablespoon | 3.5 | 20 |
| Tofu (raw, firm) | ˝ cup | 3.4 | 20 |
| Spinach (boiled, drained) | ˝ cup | 3.2 | 20 |
| Spinach (canned, drained solids) | ˝ cup | 2.5 | 10 |
| Black-eyed peas (cowpeas) (boiled) | ˝ cup | 1.8 | 10 |
| Spinach (frozen, chopped, boiled) | ˝ cup | 1.9 | 10 |
| Grits (white, enriched | 1 cup | 1.5 | 8 |
| Raisins (seedless, packed) | ˝ cup | 1.5 | 8 |
| Whole wheat bread | 1 slice | 0.9 | 6 |
| White bread (enriched) | 1 slice | 0.9 | 6 |
References
- ↑ Rockey D, Cello J (1993). "Evaluation of the gastrointestinal tract in patients with iron-deficiency anemia". N Engl J Med. 329 (23): 1691–5. PMID 8179652.
- ↑ Rimon E, Kagansky N, Kagansky M, Mechnick L, Mashiah T, Namir M, Levy S (2005). "Are we giving too much iron? Low-dose iron therapy is effective in octogenarians". Am J Med. 118 (10): 1142–7. doi:10.1016/j.amjmed.2005.01.065. PMID 16194646.
- ↑ Olivares M, Pizarro F, Pineda O, Name JJ, Hertrampf E, Walter T. (1997). "Milk inhibits and ascorbic acid favors ferrous bis-glycine chelate bioavailability in humans". J Nutr. 127 (7): 1407–11. PMID 9202099. Unknown parameter
|month=ignored (help) - ↑ http://www.globalrph.com/irondextran.htm
- ↑ James P. Kushner, John P. Porter and Nancy F. Olivieri (2001). "Secondary Iron Overload". Hematology. PMID 11722978. http://asheducationbook.hematologylibrary.org/cgi/content/full/2001/1/47
- ↑ Vaucher P, Druais PL, Waldvogel S, Favrat B (2012). "Effect of iron supplementation on fatigue in nonanemic menstruating women with low ferritin: a randomized controlled trial". CMAJ. 184 (11): 1247–54. doi:10.1503/cmaj.110950. PMC 3414597. PMID 22777991.