Iron is an essential nutrient that your body needs to make blood cells and proteins. Your doctor may prescribe iron supplements if you have iron-deficiency anemia caused by lack of dietary iron, blood loss or chronic disease. Dizziness when taking iron supplements may sometimes, but not always, indicate a life-threatening reaction to iron. Do not take iron supplements without your doctor's approval.
Iron Supplement Side Effects
Dizziness may occur as a side effect of iron supplementation. Other side effects of taking iron supplements include upset stomach, constipation, nausea and vomiting. You may become dizzy after intravenous iron injections or after taking iron supplements by mouth. Talk to your doctor as soon as possible if you experience dizziness with iron supplementation, because it may indicate iron poisoning. Other signs of iron poisoning include metallic taste, fatigue, shortness of breath, severe vomiting and grayish skin color.
Dizziness and other iron supplement side effects can be reduced by taking the supplements with food. Taking iron with foods may reduce its absorption, so you should ideally take iron on an empty stomach; if you must take iron with food to tolerate the side effects, you should avoid taking it with coffee, tea, dairy products and cereals. Side effects of iron may also be reduced by switching to enteric-coated or controlled-release iron products, although these are also more difficult for the body to absorb than regular iron.
Although iron supplements are "likely safe" for most people when taken at recommended dosages, high doses of iron are unsafe and may cause poisoning, especially in children, according to MedlinePlus. Unless you're being treated for iron deficiency, maximum daily intake should not exceed 45 mg/day, or 40 mg if you're younger than 14. Doses as low as 60 mg can be fatal, so call the poison control center if you suspect that you or someone else has taken more than the recommended amount of iron.
Taking iron supplements to correct iron-deficiency anemia can cause dizziness, but iron-deficiency anemia itself can make you feel dizzy. If you have other minor or serious health conditions or take other medications in addition to iron supplements, it is also possible that another condition or medication is responsible for your dizziness. Low blood pressure, dehydration, multiple sclerosis, Meniere's disease, bleeding in the brain and a number of medications may cause dizziness. Consult your doctor if you experience dizziness for the first time or feel dizzy after taking a medication.