What Happens After You Drink Magnesium Citrate?

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Magnesium citrate is an over-the-counter laxative formulated as an oral liquid but also available as dissolving tablets. The primary use is as a remedy for acute constipation. Your physician may also recommend this laxative to prepare you for a colonoscopy procedure. In either event, the solution is intended to empty your bowels. Aside from the intended result, use of magnesium citrate may also cause side effects. Before taking supplemental magnesium citrate, consult your physician.


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Immediate Effects

Magnesium citrate works by pulling water into your small intestine, which stimulates the normal movement of broken-down food product into your large intestine for stool bulking. Within 30 minutes to 3 hours after taking your dose, a bowel movement occurs. Stool formation and elimination can be slowed by taking the solution with food. However, if you intend to get quick results, take the solution on an empty stomach with a full glass of water.


Possible Side Effects

The most common side effects associated with taking magnesium citrate include diarrhea and stomach discomfort. Allergic reactions like rash, itching or swelling, blood in stool, dizziness, irregular heartbeat, weakness and severe diarrhea indicate severe side effects and you should seek medical attention immediately. Magnesium citrate is a laxative and therefore increases your risk of fluid and electrolyte loss. Dehydration may occur after taking this solution. Replace lost fluids by drinking several extra glasses of water or sports drinks while you are taking magnesium citrate.


Possible Interactions

Magnesium citrate contains the mineral magnesium and therefore may cause drug interactions if you take other medications. Antiobiotics, blood pressure medications, pain relievers, diuretics, medications for diabetes and some hormone replacement drugs can interact with magnesium citrate. Consult your physician before taking magnesium citrate to determine possible interactions with other supplements or medications.


Additional Considerations

Follow package labeling instructions for dosing and duration of use. Don't take over-the-counter magnesium citrate for longer than one week unless otherwise advised by your physician. Pregnant or breast-feeding women shouldn't take magnesium citrate unless under a doctor's orders to do so. Magnesium citrate may worsen abdominal pain, nausea, vomiting or rectal bleeding, so you shouldn't take it if you have these symptoms. If you have existing health conditions such as heart or kidney disease, taking magnesium citrate may cause complications such as disturbed heart rhythm or high levels of magnesium or potassium in your blood.