What Are the Side Effects of Iron Pills?

Iron supplements have several common side effects.
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Without sufficient iron, your body cannot produce the number of normal red blood cells needed to keep you healthy. Your doctor may recommend that you take iron pills, but you should be aware there are side effects of iron pills and you may even experience feeling worse after taking iron supplements.



Iron pills, available as various ferrous ion salts, can be beneficial to treat a deficiency with the proper dosage but taking too much can result in health risks of toxicity, including acute liver damage.

How Much Do You Need?

Iron is an essential component of hemoglobin, the protein in red blood cells that transfers oxygen from your lungs to every tissue in your body. Iron supports muscle contraction and helps maintain healthy connective tissue. It is also necessary for neurological development, synthesis of hormones and proper growth.

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The amount of iron you need on a daily basis depends on your age and gender. The National Institutes of Health lists the recommended dietary allowance necessary to meet your nutritional requirements. The average amount for adults 19 years of age and older is between 8 and 18 milligrams.


Most people get sufficient iron from their diet. However, because iron is primarily found in animal products, people who are on a restricted diet or are vegetarians may have low iron levels. In addition, certain conditions may increase your need for iron, according to Mayo Clinic. Some of these include:

  • Bleeding problems, such as from

    peptic ulcer, colon polyps or hiatal hernia

  • Burns

  • Kidney dialysis

  • Intestinal diseases that inhibit absorption. such as celiac disease

  • Stomach problems or surgical stomach removal

  • Medications used to increase your red blood cell count


Read More: Foods That Inhibit Iron Absorption

Should You Take Iron Pills?

Despite eating a balanced diet, you may discover that your body has depleted its stores of iron. This can result in iron deficiency anemia symptoms, according to Mayo Clinic, and may include:

  • Extreme fatigue and weakness
  • Pale skin
  • Chest pain, fast heartbeat or shortness of breath
  • Headache or dizziness
  • Cold hands and feet
  • Inflammation or soreness of your tongue
  • Brittle nails
  • Cravings for unusual substances, such as dirt or ice
  • Poor appetite, especially in infants and children


Read More: 3 Fast Ways of Getting Iron in the Blood

To correct iron deficiency, you may need to take iron supplements. It is important to make sure you take the correct dosage because too much iron can be dangerous. Excessive iron from supplements can accumulate in your organs and could result in adverse health complications including damage to your liver, warns Mayo Clinic.



Because of the inherent danger of overdosing with iron supplements, upper limits have been established as a guideline, according to NIH. Be sure to read the labels before taking any supplements to make certain that you are within the safety range of 45 milligrams of iron for adults.

Iron supplements are available in stand-alone forms, including tablets, capsules, powders and liquids, or combined with other vitamins or minerals. Formulations can differ significantly in their content of iron.


Side Effects of Iron Pills

Iron pills, if taken correctly, can replenish the iron in your blood to normal after about two months, but MedlinePlus suggests you should continue to take the supplements for another six to 12 months to build up the iron stores in your body's bone marrow. If you think you are feeling worse after taking iron supplements, it's common to experience some side effects of iron pills — ferrous sulfate, ferrous fumarate and ferrous gluconate forms included. According to MedlinePlus, these are some symptoms from taking iron supplements:


  • Urine color is dark
  • Constipation or diarrhea — Drink plenty of fluids and include adequate amounts of fiber in your diet to combat this symptom
  • Gastrointestinal discomfort — Take iron pills with meals to avoid symptoms of nausea, suggests MedlinePlus.
  • Black stools

You shouldn't be alarmed if your stools are very dark. This is one of the signs iron pills are working correctly. But let your doctor know if:


  • Stools are tarry-looking
  • Red streaks are present in your stool
  • You have cramps, sharp pains or soreness in your stomach

With higher doses, nausea and vomiting may occur. If you are taking iron in a liquid form, tooth staining may be a side effect. Try mixing the iron with a liquid and drinking the solution through a straw.


Severe Iron Toxicity

Taking an extremely higher than recommended amount of iron supplements could result in a severe iron overdose. Accidental poisonings can happen if a child accidentally eats too many pediatric multivitamins or adult prenatal vitamins, warns MedlinePlus. Symptoms of an iron overdose can affect the entire body and include:

  • Stomach and intestines: liver damage, nausea and vomiting blood, metallic taste in mouth, black bloody stools
  • Respiratory system: buildup of fluids in the lungs
  • Heart: low blood pressure, fast and weak heartbeat, shock, dehydration
  • Nervous system: chills, fever, seizures, headache, drowsiness, apathy, coma
  • Skin: bluish-colored lips, fingernails and palms of hands; skin flushing, pale skin

Symptoms of iron toxicity may decrease in a few hours, then return again after one or more days.




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