Magnesium Citrate

 Action Attracts and retains water in intestinal lumen, thereby increasing intraluminal pressure and inducing urge to defecate.

 Indications Short-term treatment of constipation; evacuation of colon for rectal and bowel evaluations.

 Contraindications Hypersensitivity to any ingredient; nausea, vomiting or other symptoms of appendicitis; acute surgical abdomen; fecal impaction; intestinal obstruction; ndiagnosed abdominal pain; intestinal bleeding; renal disease.

 Route/Dosage

ADULTS: PO 1 glassful (approximately 240 ml) prn. CHILDREN 2–6 YR: PO 4–12 ml. CHILDREN 6–12 YR: PO 50–100 ml. Repeat if necessary.

 Interactions

Nitrofurantoin: Reduced anti-infective action. Penicillamine: Reduced action of penicillamine. Tetracyclines: Impaired absorption of tetracyclines.

 Lab Test Interferences None well documented.

 Adverse Reactions

CV: Palpitations. CNS: Dizziness; fainting. GI: Excessive bowel activity (eg, cramping, diarrhea, nausea, vomiting); perianal irritation; bloating; flatulence; abdominal cramping. OTHER: Sweating; weakness; fluid and electrolyte imbalance.

 Precautions

Pregnancy: Pregnancy category undetermined. Lactation: Undetermined. Children: Exercise caution; consult physician. One 6-week old infant developed magnesium poisoning after several doses for constipation. Abuse/dependency: Chronic use of laxatives may lead to laxative dependency, which may result in fluid and electrolyte imbalances, steatorrhea, osteomalacia and vitamin and mineral deficiencies. Fluid and electrolyte imbalance: Excessive laxative use may lead to significant fluid and electrolyte imbalance. Rectal bleeding or failure to respond: May indicate serious condition requiring further attention. Renal impairment: Avoid in patients with renal dysfunction. Hypermagnesemia and toxicity may occur due to decreased clearance of magnesium ion.

 Administration/Storage

• Chilling medication or giving with ice may improve palatability.
• Administer on empty stomach and give with full glass of water to increase effectiveness of medication.
• Store in tightly closed container in cool dry place.

 Assessment/Interventions

• Obtain patient history, including drug history and any known allergies. Note symptoms of appendicitis, fecal impaction, renal disease or small bowel obstruction.
• Observe for distended abdomen and auscultate for presence of bowel sounds.
• Monitor for electrolyte imbalances and dehydration.
• If nausea, diarrhea, abdominal distention, increased abdominal pain or rectal bleeding occur, notify physician.

 Patient/Family Education

• Explain that drug should not be used routinely for constipation; ependence can result.
• Instruct patient to report any of these symptoms to physician: nrelieved constipation, vomiting, diarrhea, abdominal fullness, rectal bleeding, dizziness and muscle cramps.
• Review information on proper use and storage of medication.