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Drug Profile

The information on this site is intended to supplement and enhance, not replace, the advice of a physician who is familiar with your medical history. Decisions about your health should always be made ONLY after detailed conversation with your doctor.

Generic drug name: ferrous fumarate (FAIR us FEW mar ate)
Brand name(s): FEOSTAT
GENERIC: available FAMILY: Minerals
Find the drug label by searching at DailyMed.

Generic drug name: ferrous gluconate (FAIR us GLUE koe nate)
Brand name(s): FERGON
GENERIC: available FAMILY: Minerals
Find the drug label by searching at DailyMed.

Generic drug name: ferrous sulfate (FAIR us SUL phate)
Brand name(s): FEOSOL, SLOW FE
GENERIC: available FAMILY: Minerals
Find the drug label by searching at DailyMed.

Pregnancy and Breast-feeding Warnings [top]

Minerals taken at the level that supplies normal body needs (not megadoses) do not pose a risk to the fetus or the nursing infant.

Facts About This Drug [top]

 

...
FOODS HIGH IN IRON
Organ meats, red meat, oysters (all are also high in cholesterol and/or fat), fish, green leafy vegetables, peas, brewer’s yeast, wheat germ, certain dried beans and fruits. Iron from meats is also absorbed an average of five times better than iron from vegetables.
3 ½ ounces calves’ liver 14 milligrams iron
1 lean hamburger 3.9 milligrams iron
3 ½ ounces chickpeas 3 milligrams iron

 

FOODS HIGH IN IRON
Organ meats, red meat, oysters (all are also high in cholesterol and/or fat), fish, green leafy vegetables, peas, brewer’s yeast, wheat germ, certain dried beans and fruits. Iron from meats is also absorbed an average of five times better than iron from vegetables.
3 ½ ounces calves’ liver 14 milligrams iron
1 lean hamburger 3.9 milligrams iron
3 ½ ounces chickpeas 3 milligrams iron
½ cup cooked lima beans 3 milligrams iron

Iron is a mineral that your body needs to manufacture hemoglobin, a substance in red blood cells that carries oxygen throughout the body. A lack of iron causes anemia, a condition in which the body has too few red blood cells, too little hemoglobin, or too little blood. Iron is found in many foods (see box above), and a well-balanced diet with a variety of foods should supply all the iron that your body needs. There is no reason to take an iron supplement unless you have a low iron count or iron-deficiency anemia. The recommended dietary allowance (RDA) for adults over the age of 50 is eight milligrams per day.

Adults generally become iron-deficient from blood loss, rather than from a lack of iron in their diet. If your doctor says that you have iron-deficiency anemia, she or he must determine the site of the blood loss.

If you have iron-deficiency anemia due to blood loss, you should add iron-rich foods to your diet as well as take an iron supplement. When comparing iron supplements, you should always check how much elemental (pure) iron they contain. For example, a 324 milligram ferrous sulfate tablet contains 65 milligrams of elemental iron, while a 320 milligram ferrous gluconate tablet contains 37 milligrams of elemental iron, and a 100 milligram ferrous fumarate tablet contains 33 milligrams of elemental iron. You should start out with a supplement containing ferrous sulfate, rather than one made of ferrous gluconate or ferrous fumarate.[1]

Do not use iron supplements that also contain other minerals such as calcium and magnesium, which can interfere with your body’s absorption of iron. Also, do not use enteric-coated tablets (tablets coated so they do not dissolve in your stomach) or timed-release products, because your body does not absorb them evenly. Do not take an iron supplement at the same time as eating foods high in fiber or calcium.

By two weeks after you begin to take an iron supplement, your red blood cell count should improve. If there is no improvement after three to four weeks, ask your doctor to reevaluate your situation. If you are anemic, you might need to take iron supplements for six months or longer to replenish the body’s supply. If the cause of your iron deficiency is poor absorption of iron, a rare problem, you may have to take an iron supplement for longer than six months.

If you do not have a low iron count or iron-deficiency anemia, there is no reason for you to take an iron supplement. Your body saves iron and cannot get rid of extra iron except by bleeding. Taking too much iron can cause an iron overload in the body and damage to your liver, heart, or kidneys.[2]

The British Expert Group on Vitamins and Minerals has found that:

For guidance purposes, a supplemental intake of approximately 17 mg/day would not be expected to produce adverse effects in the majority of people....This is based on data referring to ferrous iron (Fe II), which is the form of iron used in supplements currently available in this country. A safe upper level for total iron has not been estimated, as gastrointestinal effects are associated with iron in supplements rather than in foods. The guidance value of 17 mg/day calculated above, does not apply to the small proportion of the population who have increased susceptibility to iron overload, via a mechanism of unregulated (increased) absorption from the diet, associated with the homozygous haemochromatosis genotype (estimated prevalence, approximately 0.4 percent in Caucasian populations).[3]

Before You Use This Drug [top]

Do not use if you have or have had:

  • diseases of iron overload (hemochromatosis, hemosiderosis)
  • thalassemia (a hereditary anemia)
  • porphyria
  • other anemia conditions unless accompanied by iron deficiency

Tell your doctor if you have or have had:

  • asthma
  • heart disease
  • alcohol dependence
  • allergies to drugs
  • pregnancy or are breast-feeding
  • disease of the intestines
  • liver disease (hepatitis)
  • kidney disease
  • peptic ulcer
  • recent blood transfusion
  • rheumatoid arthritis
  • sensitivity to iron

Tell your doctor about any other drugs you take, including aspirin, herbs, vitamins, and other nonprescription products.

When You Use This Drug [top]

  • Your stools will probably turn black. This is a normal side effect and no cause for concern.
  • Take iron supplements one hour before or two hours after eating dairy products, eggs, coffee, tea, whole-grain breads and cereals, antacids, or calcium supplements.
  • Avoid regular use of large amounts of iron supplements several times daily for more than six months unless approved by your doctor.
  • Extended-release dosage forms may not release iron properly; check with your doctor if stools are not black during therapy.
  • Iron supplements can stain your teeth. To prevent, reduce, or remove iron stains on your teeth:
    • Dilute liquid forms of iron preparations in water or fruit juice.
    • Use a straw (for liquid forms).
    • Place dropper doses well back on tongue (for liquid forms).
    • Brush teeth with baking soda or 3% hydrogen peroxide.

How to Use This Drug [top]

  • Take on an empty stomach, at least one hour before, or two hours after, meals. If the iron upsets your stomach, try taking it with food instead. Take with a full glass (eight ounces) of water or fruit juice.
  • If you miss a dose, take it as soon as you remember, but skip it if it is almost time for the next dose. Do not take double doses.
  • Do not share your medication with others.
  • Take the drug at the same time(s) each day.
  • Do not break, chew, or crush long-acting forms of this drug.
  • For oral suspension: Shake well before using.
  • For chewable tablets: Chew well before swallowing.

Interactions with Other Drugs [top]

The following drugs, biologics (e.g., vaccines, therapeutic antibodies), or foods are listed in Evaluations of Drug Interactions 2003 as causing “highly clinically significant” or “clinically significant” interactions when used together with any of the drugs in this section. In some sections with multiple drugs, the interaction may have been reported for one but not all drugs in this section, but we include the interaction because the drugs in this section are similar to one another. We have also included potentially serious interactions listed in the drug’s FDA-approved professional package insert or in published medical journal articles. There may be other drugs, especially those in the families of drugs listed below, that also will react with this drug to cause severe adverse effects. Make sure to tell your doctor and pharmacist the drugs you are taking and tell them if you are taking any of these interacting drugs:

ACHROMYCIN, ACTONEL, ALDOMET, AVELOX, cefdinir, CELLCEPT, CHIBROXIN, CILOXAN, CIPRO, ciprofloxacin, COMTAN, CUPRIMINE, DEPEN, enoxacin, entacapone, LARODOPA, LEVAQUIN, levodopa, levofloxacin, lomefloxacin, MAXAQUIN, methyldopa, moxifloxacin, mycophenolate, norfloxacin, NOROXIN, OMNICEF, PANMYCIN, PENETREX, penicillamine, risedronate, SINEMET, SUMYCIN, TERRAMYCIN, tetracycline, trovafloxacin, TROVAN.

Adverse Effects [top]

Call your doctor immediately if you experience:

  • abdominal or stomach pain, cramping, or soreness
  • chest or throat pain, especially when swallowing
  • stools containing blood

Call your doctor if these symptoms continue:

  • constipation
  • diarrhea
  • nausea or vomiting
  • darkened urine
  • teeth staining
  • heartburn

Signs of overdose:

  • Early symptoms:
    • diarrhea, sometimes containing blood
    • fever
    • severe nausea
    • sharp stomach pain or cramping
    • severe vomiting, sometimes containing blood
  • Late symptoms:
    • bluish-colored lips, fingernails, or palms of hands
    • drowsiness
    • pale, clammy skin
    • seizures
    • rapid and shallow breathing
    • unusual tiredness or weakness
    • weak and fast heartbeat

If you suspect an overdose, call this number to contact your poison control center: (800) 222-1222.

Periodic Tests[top]

Ask your doctor which of these tests should be done periodically while you are taking this drug:

  • ferritin concentration in the blood
  • hemoglobin and hematocrit tests
  • iron concentration in the blood
  • reticulocyte (young red blood cell) counts
  • total iron binding capacity (TIBC)

last reviewed May 31, 2021