Common side effects associated with iron supplements include stomach pain, constipation, diarrhea, nausea and vomiting. High doses of iron have the potential to be fatal, according to WebMD.Continue Reading
Poisoning from a high iron dose may cause stomach or intestinal distress, liver failure and dangerously low blood pressure. If there is suspicion that an adult or child has taken too much iron, immediate consultation with a health care professional or poison control center is necessary, instructs WebMD. Some studies suggest that high iron intake may lead to heart disease; however, these are controversial studies, and research conducted on this issue is insufficient as of 2015.
Women who are pregnant or breastfeeding and taking high doses of iron may suffer from nausea and vomiting. Iron supplements are also linked to worsening conditions, such as ulcerative colitis or Crohn's disease, as noted by WebMD. People with hemoglobin diseases need to be careful with iron as it may overload their systems.
Taking iron supplements with food sometimes prevents symptoms of an upset stomach; however, the body may not absorb the iron as well if it is taken with food, according to WebMD. It is best to take iron on an empty stomach when possible.Learn more about Side Effects