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. Follow carefully any diet program your health care professional may recommend. The best dietary sources of magnesium include green leafy vegetables, nuts, peas, beans, and cereal grains in which the germ or outer layers have not been removed. Hard water has been found to contain more magnesium than soft water.