Iron is an essential nutrient that transports oxygen throughout the body in red blood cells. Iron deficiency results from inadequate intake, inadequate absorption, excessive losses or some combination of the three. Treatment begins with iron supplements. In rare cases, iron supplements may cause itching. If you experience this, contact your doctor immediately.
Itching in response to iron supplements suggests an allergic reaction. Iron in supplements is attached to another molecule, usually a salt or a sugar. Common examples include sulfate, fumarate, gluconate, dextran and sucrose. Some iron supplements may be colored with dyes such as the yellow dye, tartrazine. These substances may provoke an allergic reaction. If you have a history of allergic reactions to iron supplements, other drugs or substances in the food or the environment, share this information with your doctor before you take iron supplements.
Itching is usually accompanied by other symptoms. MayoClinic.com says “more common” symptoms include backache; headache; groin, side, muscle or chest pain; fever with sweating, chills, dizziness, fainting, flushing, fast heartbeat, nausea or vomiting; abdominal pain or soreness; skin redness; skin rash or hives; swelling of the mouth or throat and numbness and pain or tingling of the hands and feet. “Less common” symptoms include double vision, generalized sense of being unwell and weakness without dizziness or fainting.
Contact your doctor as soon as itching occurs. She may tell you to go directly to the emergency room or she may tell you to remain at home unless your symptoms worsen. If you remain at home, arrange to have a companion with you for at least 60 minutes in case your symptoms worsen and you become unable to seek assistance on your own. Do not take the supplement again unless your doctor tells you it is OK to do so.
If you have a history of allergies, always review the ingredients of any medication that you take, including iron supplements. Different brands or formulas of the same product often contain different ingredients. Never take more than the recommended dose of iron supplements. If you miss a dose, skip it. Never double doses because this increases the risk of an allergic reaction.
Allergic reactions occur more often with injectable iron supplements compared to oral supplements. You may be asked to remain in the office or facility for 30 to 60 minutes of observation after you receive an iron injection. Complying with these instructions will not prevent an allergic reaction, but it will facilitate prompt intervention if one occurs. Always keep iron supplements out of reach of children. MedlinePlus says that accidental overdose of products that contain iron is one of the “leading causes” of fatal poisoning in children under 6. If your child manifests itching, consider unauthorized ingestion of iron or another medication as a possible cause.
- Harrison's Principles of Internal Medicine, 23rd Edition; Anthony S. Fauci, M.D. et al.; 2008
- MedlinePlus: Ferrous Sulfate (Iron)
- MayoClinic.com: Iron Supplement (Oral Route, Parenteral Route): Side Effects