Pharmacy Services

Magnesium Sulfate Injection

May 31, 2013

FDA is notifying health care providers that the use of magnesium sulfate injection in preterm labor is not recommended for more than 5-7 days. Neonatal bone changes and low calcium levels may be associated with the use of prolonged magnesium sulfate injection in pregnant women. Altered magnesium, phosphorus, calcium, and osteocalcin levels have also been seen in neonates following prolonged in utero exposure to magnesium sulfate. The use of magnesium sulfate injection for preterm labor is not a labeled indication; however, the product labeling is being updated to include warnings on prolonged use of magnesium sulfate injection in pregnant patients.

Several case reports in the literature, which were also reported to FDA, have shown adverse bone changes and altered laboratory values in neonates. The laboratory values return to baseline soon after birth of the infant, but the long-term consequences of the bone changes and abnormal laboratory values are unclear.

Report any related adverse events to FDA’s MedWatch Adverse Event Reporting program online:

Additional information is available at the following links:

May 31, 2013. University of Utah Drug Information Service. Copyright 2013, Drug Information Service, University of Utah, Salt Lake City, Utah.