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nausea, vomiting, diarrhea, and other side effects.
Doses less than 350 mg daily are safe for most adults. When taken in very large amounts, magnesium is POSSIBLY UNSAFE. Large doses might cause too much magnesium to build up in the body, causing serious side effects including an irregular heartbeat, low blood pressure, confusion, slowed breathing, coma, and death.
Special Precautions & Warnings:Pregnancy and breast-feeding: Magnesium is LIKELY SAFE for pregnant or breast-feeding women when taken in doses less than 350 mg daily. Magnesium is POSSIBLY SAFE when injected as a shot or intravenously (by IV) before delivery. Magnesium is POSSIBLY UNSAFE when taken by mouth or by IV in high doses.
Children: Magnesium is LIKELY SAFE for most people when taken by mouth appropriately or when the prescription-only, injectable product is used correctly. Magnesium is safe when taken in doses less than 65 mg for children 1-3 years, 110 mg for children 4-8 years, and 350 mg for children older than 8 years. Magnesium is LIKELY UNSAFE when taken in higher doses.
Alcoholism: Alcohol abuse increases the risk for magnesium deficiency.
Bleeding disorders: Magnesium seem to slow blood clotting. In theory, taking magnesium might increase the risk of bleeding or bruising in people with bleeding disorders.
Diabetes: Diabetes increases the risk for magnesium deficiency. Poorly controlled diabetes reduces how much magnesium the body absorbs.
Elderly: The elderly are at risk for magnesium deficiency due to reduced magnesium absorption by the body and often the presence of diseases that also affect magnesium absorption.
Heart block: High doses of magnesium (typically delivered by IV) should not be given to people with heart block.
Diseases that affect magnesium absorption: How much magnesium the body absorbs can be reduces by many conditions, including stomach infections, immune diseases, inflammatory bowel disease and others.
Kidney problems, such as kidney failure: Kidneys that don't work well have trouble clearing magnesium from the body. Taking extra magnesium can cause magnesium to build up to dangerous levels. Don't take magnesium if you have kidney problems.
Restless leg syndrome: People with restless leg syndrome might have high magnesium levels. But it's not clear if magnesium is the cause for this condition, as people with restless leg syndrome have also had magnesium deficiency.
Report Problems to the Food and Drug Administration
You are encouraged to report negative side effects of prescription drugs to the FDA. Visit the FDA MedWatch website or call 1-800-FDA-1088.