The Safety of Magnesium Supplements

Magnesium is a dietary mineral your body uses to maintain a variety of functions, including heart rate contraction, bone development and immune system, muscle and nerve function. Each day, adults should consume between 310 and 420 milligrams of magnesium. Though it's best to get your daily dose of this nutrient from a healthy diet of magnesium-rich foods, such as halibut, almonds, soybeans and spinach, taking magnesium supplements may help you reach the recommended intake of this mineral. Talk with your medical provider about the safety of magnesium supplements before beginning treatment.


Adverse Effects

When used as directed, magnesium supplements typically do not cause side effects. However, some people experience mild stomach upset, nausea or vomiting after taking a dose of magnesium, and these supplements may also irritate your intestinal tract and cause diarrhea, appetite loss, abdominal cramping or bloating. If you experience recurrent bouts of diarrhea, you could become dehydrated. Contact your doctor for further evaluation and care if these side effects persist or become severe.


Taking more than the recommended dose of magnesium may result in adverse effects. High blood levels of magnesium can cause overdose symptoms include vomiting, reduced heart rate, confusion, dizziness, blurred vision, difficulty breathing, low blood pressure and coma. In the absence of prompt medical intervention, a magnesium overdose may cause fatal health complications. Seek emergency medical care if you believe you've taken too much magnesium or if you exhibit any symptoms of overdose.

Drug Interactions

Let your medical provider know if you are taking any other drug or supplement before you begin treatment with magnesium. Using magnesium supplements at the same time as certain antibiotics, including doxycycline, minocycline, ciprofloxacin and tetracycline, should be avoided because the extra magnesium may make it harder for your body to absorb the antibiotic. Taking magnesium together with calcium channel blockers or blood pressure medications may increase your risk of experiencing side effects, including dizziness or nausea. Magnesium may also reduce the effectiveness of other medications, including tiludronate, alendronate and levothyroxine.


Magnesium supplements may not be appropriate for people with certain health conditions, including a personal history of kidney or heart disease, so do not use these supplements without first consulting your doctor. If you have impaired kidney function, you may not be able to clear excess magnesium efficiently from the body, increasing the risk for magnesium toxicity.


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This article reflects the views of the writer and does not necessarily reflect the views of Jillian Michaels or