DBL Magnesium Sulfate Special Precautions

Magnesium sulfate heptahydrate may precipitate an acute myasthenic crisis. Sensitivity to parenteral magnesium has been reported.
Monitoring serum magnesium levels and the patient's clinical status is essential to avoid the consequences of overdosage in toxemia.
An intravenous preparation of a calcium salt (eg calcium gluconate) should be readily available for use when magnesium sulfate heptahydrate is given intravenously.
Use in renal impairment: Magnesium should be administered with caution in patients with impaired renal function, since the risk of hypermagnesaemia is increased in these patients.
Effects on laboratory tests: Monitoring of serum magnesium levels is advised at periodic intervals during therapy to ensure that normal serum magnesium levels are not exceeded.
The patellar reflex should be tested prior to administering repeat doses of magnesium sulfate heptahydrate. Suppression of the reflex is an indication of magnesium intoxication.
Respiration rate should be determined and should be at least 16 per minute prior to each dose of magnesium sulfate heptahydrate, as respiratory depression is the most critical side effect of the medication.
Urine output should be monitored and should be at least 100 mL during the four hours preceding dosing, to ensure adequate excretion of magnesium.
Effects on Ability to Drive and Use Machines: The effects of this medicine on a person's ability to drive and use machines were not assessed as part of its registration.
Use in Children: No data available.
Use in the Elderly: No data available.