Although a balanced diet usually supplies all the magnesium a person needs, magnesium supplements may be needed by patients who have lost magnesium because of illness or treatment with certain medicines. Lack of magnesium may lead to irritability, muscle weakness, and irregular heartbeat.
Injectable magnesium is given only by or under the supervision of a health care professional.
Some oral magnesium preparations are available only with a prescription. Others are available without a prescription. If you are taking this dietary supplement without a prescription, carefully read and follow any precautions on the label. Tell your health care professional if you have ever had any unusual or allergic reaction to magnesium. Also tell your health care professional if you are allergic to any other substances, such as foods, preservatives, or dyes.