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Important Note

The following information is intended to supplement, not substitute for, the expertise and judgment of your physician, pharmacist or other healthcare professional. It should not be construed to indicate that use of the drug is safe, appropriate, or effective for you. Consult your healthcare professional before using this drug.


(mag-NEE-zee-um SULL-fate)


This medication is used to control seizures in pregnancy, to treat low magnesium levels and problems related to kidney conditions (nephritis) in children. This drug is also used for preventing premature contractions in pregnancy and to treat heart attack and asthma patients.

How To Use

Use exactly as directed by vein (IV) or injection into muscle (IM). Dosage is adjusted according to individual requirements and the response to treatment.

Side Effects

Unlikely but report: flushing, sweating, muscle weakness, dizziness, drowsiness, muscle weakness, slowed/shallow breathing or other breathing trouble. If you notice other effects not listed above, contact your doctor or pharmacist.


Before using this drug, tell your doctor your medical history, including: allergies (especially drug allergies), kidney or heart disease, low blood calcium, myasthenia gravis. Avoid alcohol intake, since the possible drowsiness effect of this medication may be increased. Caution when performing tasks requiring mental alertness. While magnesium use is safe during pregnancy, continuous IV use near the time of delivery may result in newborn adverse effects. Do not use magnesium during the final two hours before delivery. This drug is excreted into breast milk. Consult your doctor before breast-feeding.

Drug Interactions

Tell your doctor of all nonprescription or prescription medication you use, especially of: nerve blocking medicines (e.g., pancuronium). Medications that can increase the drowsiness effect of this drug include: sedatives, tranquilizers, drugs for sleep, narcotic pain relievers, psychiatric medications (e.g., chlorpromazine), certain antidepressants (e.g., amitriptyline), certain antihistamines, muscle relaxants, anti-seizure medications. Do not start or stop any medicine without doctor or pharmacist approval.


If overdose is suspected, contact your local poison control center or emergency room immediately. Symptoms of overdose may include nausea, vomiting, slow heartbeat, flushing, decreased alertness, confusion, muscle weakness, and loss of consciousness.


Blood tests are performed to monitor the magnesium levels. Fetal response is also checked if this drug is used in pregnancy.

Missed Dose

If you miss a dose, consult your doctor or pharmacist.


Store at room temperature away from sunlight and moisture.

Medical Alert

Your condition can cause complications in a medical emergency. For enrollment information call MedicAlert at 1-800-854-1166 (USA), or 1-800-668-1507 (Canada).