In the 2005 edition of "Modern Nutrition in Health and Disease," director of the USDA's Jean B. Mayer human nutrition laboratory, Richard J. Wood, Ph.D. defines iron as a "biologically essential element involved in the metabolism of all living organisms." While all people require iron, some people do not meet their requirement through a standard diet. In this case, your doctor may recommend iron supplements. However, iron supplements may interact with other supplements and medications you take.
Types
Doctors prescribe three types of iron supplements. Patients take oral iron supplements such as ferrous sulfate, ferrous fumarate and ferrous gluconate at home or on the go. Intramuscular or intravenous iron supplements must be administered in a doctor's office, clinic or hospital. Most interactions occur in the gastrointestinal tract and intramuscular and intravenous iron supplements bypass this route.
Significance
Iron supplements interfere with your body's ability to absorb quinolone and tetracycline antibiotics such as ciprofloxacin, enoxacin, norfloxacin, sparfloxacin, trovafloxacin, grepafloxacin, demeclocycline and minocycline. They have a similar effect on bisphosphonates used to treat and prevent osteoporosis, levothyroxine for low thyroid, methyldopa for Parkinson's disease, mycophenylate mofetil for organ transplant rejection and penicillamine for Wilson's disease and rheumatoid arthritis. Calcium supplements, zinc supplements, antacids and acid suppressor medications such as H2 blockers and proton pump inhibitors interfere with your body's ability to absorb iron. Chloramphenicol, an antibiotic, may affect your body's ability to use iron to make red blood cells, although it does not interact with the supplement itself.
Time Frame
Take oral iron supplements at least two hours before or two hours after you take other drugs. In the case of tetracycline antibiotics, MedlinePlus says to wait four hours after taking iron supplements. Ideally, you should also take oral iron supplements on an empty stomach, at least one hour before or two hours after a meal. If you have trouble scheduling all of your medications and meals, ask your doctor for advice.
Considerations
Some patients forget to include non-prescription drugs and supplements such as iron in their medical histories. Always tell your doctor about all over-the-counter drugs, dietary supplements and alternative remedies that you use, so your doctor can counsel you on applicable interactions. Your pharmacist is also an excellent resource on drug interactions. Use the same pharmacy for all of your medications so your pharmacist knows what you are taking.
Alternatives
If you are prescribed a medication that interferes with iron supplements, ask your doctor whether you can discontinue taking iron supplements. If your iron deficiency is not severe or symptomatic, your doctor may agree that is safe for you to stop taking iron, at least for a short period of time. If the interaction is severe and it is not safe for you to stop taking iron, your doctor may prescribe intramuscular or intravenous iron instead of oral supplements.
References
- "Modern Nutrition in Health and Disease, 10th Edition"; Maurice E. Shils, M.D., D.Sc. et al.; 2005
- MedlinePlus: Iron
- National Anemia Action Council: A Patient's Guide to Oral Iron Supplements
Member Comments