magnesium citrate (Citrate of Magnesia, Citroma)

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GENERIC NAME: magnesium citrate

BRAND NAME: Citrate of Magnesia, Citroma

DRUG CLASS AND MECHANISM: Magnesium citrate is supplied as an oral tablet or liquid saline laxative. Magnesium citrate retains water in the intestines by osmosis. Increasing water in the bowel aids motility, usually producing a bowel movement within one-half to six hours.



PREPARATIONS: Liquid: 290 mg/ 5 ml. Tablet: 100 mg

STORAGE: Store magnesium citrate between temperatures 8 C and 30 C (46 F and 86 F).

PRESCRIBED FOR: Magnesium citrate is used for bowel evacuation (bowel preparation or cleansing), constipation, and bowel irregularity.


  • Adults and children 12 years of age and older: Use 195 to 300 ml of magnesium citrate with a full glass of water. It may be taken as a single dose or divided doses or may also be used with 2 to 4 tablets at bedtime.
  • Children 6 to under 12 years of age: Use 90 to 210 ml of magnesium citrate with a full glass of water; it may be taken as a single dose or divided doses.
  • Children 2 to under 6 years of age: Use 60 to 90 ml of magnesium citrate; it may be taken as a single dose or divided doses with a maximum dose of 90 ml in 24 hours.

Safe and effective use of magnesium citrate is not established for children under the age of 2.

DRUG INTERACTIONS: Magnesium citrate should not be combined with medications like eltrombopag (Promacta), doxycycline (Vibramycin), minocycline (Minocin), ciprofloxacin (Cipro), and levofloxacin (Levaquin) because magnesium citrate decreases absorption of these antibiotics and leads to decreased therapeutic effect.

Medically Reviewed by a Doctor on 10/2/2014

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