Iron overdose

Iron is a mineral found in many over-the-counter vitamin or mineral supplements. Iron overdose occurs when someone takes more than the normal or recommended amount of this mineral. This can be by accident or on purpose.

Iron overdose is particularly dangerous for children. A severe overdose can happen if a child eats adult multivitamins, such as prenatal vitamins. If the child eats too many pediatric multivitamins, the effect is usually minor.

This article is for information only. DO NOT use it to treat or manage an actual overdose. If you or someone you are with has an overdose, call your local emergency number (such as 911), or your local poison control center can be reached directly by calling the national toll-free Poison Help hotline (1-800-222-1222) from anywhere in the United States.

Poisonous Ingredient

Iron can be harmful in large amounts.

Where Found

Iron is an ingredient in many mineral and vitamin supplements. Iron supplements are also sold by themselves. Types include:

Ferrous sulfate (Feosol, Slow Fe)
Ferrous gluconate (Fergon)
Ferrous fumarate (Femiron, Feostat)

Other products may also contain iron.

Symptoms

Below are symptoms of an iron overdose in different parts of the body.

AIRWAYS AND LUNGS

Buildup of fluids in the lungs

STOMACH AND INTESTINES

These are the most common symptoms in the first 6 hours after ingestion.

Black, and possibly bloody stools
Diarrhea
Liver damage (may occur several days after the ingestion)
Metallic taste in mouth
Nausea
Vomiting blood

HEART AND BLOOD

Dehydration
Low blood pressure
Fast and weak pulse
Shock (may occur early from blood loss from the stomach or intestines, or later from the toxic effects of iron)

NERVOUS SYSTEM

Chills
Coma (decreased level of consciousness and lack of responsiveness, may occur within 1/2 hour to 1 hour after overdose)
Convulsions
Dizziness
Drowsiness
Fever
Headache
Lack of desire to do anything

SKIN

Note: Symptoms may go away in a few hours, then return again after 1 day or later.

Before Calling Emergency

Have this information ready:

Person's age, weight, and condition
Name of the product (ingredients and strength, if known)
Time it was swallowed
Amount swallowed
If the medicine was prescribed for the person

Poison Control

Your local poison control center can be reached directly by calling the national toll-free Poison Help hotline (1-800-222-1222) from anywhere in the United States. This national hotline will let you talk to experts in poisoning. They will give you further instructions.

This is a free and confidential service. All local poison control centers in the United States use this national number. You should call if you have any questions about poisoning or poison prevention. It does NOT need to be an emergency. You can call for any reason, 24 hours a day, 7 days a week.

What to Expect at the Emergency Room

Take the container to the hospital with you, if possible.

Your health care provider will measure and monitor the person's vital signs, including temperature, pulse, breathing rate, and blood pressure. Symptoms will be treated.

Tests that may be done include:

Blood and urine tests, including tests to check iron levels
Electrocardiogram (ECG)
X-ray to detect and track iron tablets in the stomach and intestines

Treatment may include:

Fluids through a vein (by IV).
Medicine to help remove iron from the body and treat symptoms. This is called 'chelation.'
Endoscopy -- camera and tube placed down the throat to view the esophagus and the stomach and to remove pills or stop internal bleeding.
Whole bowel irrigation with a special solution to quickly flush the iron through the stomach and intestines (taken by mouth or through a tube through the nose into the stomach).
Breathing support, including tube through the mouth into the lungs and connected to a breathing machine (ventilator).

Outlook (Prognosis)

There is a good chance of recovery if the person's symptoms are gone 48 hours after the iron overdose. But, severe liver damage can occur 2 to 5 days after the overdose. Some people have died up to a week after an iron overdose. The more quickly the person receives treatment, the better the chance for survival.

Iron overdose can be very severe in children. Children may sometimes eat large amounts of iron pills because they look like candy. Many manufacturers have changed their pills so they no longer look like candy.

Alternative Names

Ferrous sulfate overdose; Ferrous gluconate overdose; Ferrous fumarate overdose

References

Aronson JK. Iron salts. In: Aronson JK, ed. Meyler's Side Effects of Drugs. 16th ed. Waltham, MA: Elsevier; 2016:323-333.

Bluth MH, Pincus MR, Abraham NZ. Toxicology and therapeutic drug monitoring. In: McPherson RA, Pincus MR, eds. Henry's Clinical Diagnosis and Management by Laboratory Methods. 24th ed. Philadelphia, PA: Elsevier; 2022:chap 24.

Theobald JL, Kostic MA. Poisoning. In: Kliegman RM, Stanton BF, St. Geme JW, Schor NF, eds. Nelson Textbook of Pediatrics. 21st ed. Philadelphia, PA: Elsevier; 2020:chap 77.

Theobald JL, Mycyk MB. Iron and heavy metals. In: Walls RM, ed. Rosen's Emergency Medicine: Concepts and Clinical Practice. 10th ed. Philadelphia, PA: Elsevier; 2023:chap 146.

Review Date 11/2/2023

Updated by: Jesse Borke, MD, CPE, FAAEM, FACEP, Attending Physician at Kaiser Permanente, Orange County, CA. Also reviewed by David C. Dugdale, MD, Medical Director, Brenda Conaway, Editorial Director, and the A.D.A.M. Editorial team.