Also known as Citroma
Magnesium citrate, a magnesium preparation in salt form with citric acid, is a chemical agent used medicinally as a saline laxative and to completely empty the bowel prior to a major surgery or colonoscopy. It is available without a prescription, both as a generic or under the brand name Citromag or Citroma. It is also used in pill form as a magnesium dietary supplement. The magnesium content of magnesium citrate corresponds to about 11% by mass.Source: Wikipedia
Patients are most commonly prescribed magnesium citrate to treat chronic constipation, sharp abdominal pain, constipation, and retention of urine.