The Side Effects of Magnesium Oxide for Blood Pressure

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Magnesium supplements come in several forms, including magnesium oxide. This mineral plays many important roles in the body such as promoting normal blood pressure. Diets rich in this nutrient have been associated with a decreased risk of hypertension. While generally safe when used properly, like any supplement, use of magnesium oxide carries a risk of side effects. Do not use magnesium supplements to treat your high blood pressure without talking to your doctor.

Low Blood Pressure

Because magnesium helps lower blood pressure, taking supplements poses a risk of causing it to drop too much.This effect is more likely if you take excess amounts, or if you combine it with blood pressure medications. In the latter instance, you might need to take less of the medicine to compensate for the actions of magnesium.Talk to your doctor before adding magnesium to your treatment plan and do not make any adjustments to your medications on your own; let your doctor determine whether you require a change.

Pregnant Women and Calcium Channel Blockers

If you are pregnant and take calcium channel blockers to manage your blood pressure, do not self-treat your hypertension with magnesium. This combination increases the risk of negative side effects associated with this medication in this specific population, according to the University of Maryland Medical Center.

Dose for Managing Blood Pressure

The University of Michigan Health System reports most studies have used between 350 and 500 milligrams of magnesium to treat high blood pressure.The National Institutes of Health Office of Dietary Supplements notes a tolerable upper intake limit of 350 milligrams of supplemental magnesium. This amount does not include the magnesium obtained from foods. Taking more than this, which is sometimes required depending on the reason for use, increases the risk of negative effects associated with magnesium supplementation, such as abnormal heart rhythms and changes in mental status. The dose you need will depend on many factors, such as whether you have a demonstrated deficiency or if you use medications that affect magnesium levels. Consult your doctor for the appropriate dose and only use magnesium under his supervision.

Other Possibly Negative Effects

Do not use magnesium supplements without talking to your doctor first if you have impaired kidney function; this condition can interfere with your body’s ability to remove excess magnesium, increasing the risk of toxicity. Same goes if you have any heart conditions. Take antibiotics and your supplements at least two hours apart from each other to prevent magnesium from interfering with their absorption. Magnesium might increase the blood sugar-lowering effects of insulin and other diabetes drugs; to prevent hypoglycemia, you might require changes in your doses.