Iron overdose has been one of the leading causes of death caused by toxicological agents in children younger than 6 years. Iron is used as a pediatric or prenatal vitamin supplement and for treatment of anemia. Iron is particularly tempting to young children because it appears similar to candy. Patients with anemias that require frequent blood transfusions also are at risk for developing chronic iron toxicity.

Iron overload may develop chronically as well, especially in patients requiring multiple transfusions of red blood cells. This condition develops in patients with sickle cell disease, thalassemia, and myelodysplastic syndromes.

Calcium

Do not take if you have: allergies to calcium or antacids, high blood-calcium levels, or sarcoidosis.

Consult your doctor if you have: kidney disease, chronic constipation, colitis, diarrhea, stomach or intestinal bleeding, irregular heartbeat, or heart problems or high blood pressure for which you are taking a calcium channel blocker.

Excessively high intakes of calcium can interfere with the absorption of zinc, magnesium, iron, phosphorus and other nutrients. When calcium in the body is too high compared to magnesium, excess calcium may be deposited in the soft tissues. This may result in calcium deposits in places such as the kidneys, the arteries and the heart.

Signs of toxicity can also include: confusion, slow or irregular heart beat, bone or muscle pain, nausea and vomiting.

Boron may be toxic in doses above 100 mg. Symptoms of toxicity include: a red rash, vomiting, diarrhea, reduced circulation, and shock and then coma.

Excessive amounts of cobalt can cause nausea and damage the heart, kidneys and nerves.

ntakes in excess of 10 mg can cause vomiting, diarrhea, muscular pain, depression, irritability, nervousness and dementia.

Toxicity is low and very rare.

Zinc and copper should not be taken at the same time (take them some hours apart) unless in the form of a well balanced multivitamin and mineral supplement.