Indications

1. Treatment of magnesium deficiency in hypomagnesaemia.

2. Treatment of magnesium deficiency where the oral route of administration may be inappropriate.

3. To prevent further seizures associated with eclampsia.

Dosage and Administration

Usage: Magnesium sulphate injection will be given by injection either into a muscle (intramuscularly) or into a vein (intravenously) after being diluted. The dose depends on individual needs and responses to treatment.

Precautions & Warning:

1. Magnesium salts should be administered with caution to patients with impaired renal function; appropriate reductions in dosage should be made.

2. Parenteral magnesium should be used with caution in individuals with myasthenia gravis, to prevent an exacerbation of the condition or the precipitation of a myasthenic crisis. A risk-benefit assessment should be performed in individual cases prior to initiation of treatment.

3. Magnesium sulfate should not be used in hepatic coma if there is risk of renal failure.

4. Serum calcium levels should be routinely monitored in patients receiving magnesium sulfate.

Contraindications:

1. Hypersensitivity to the Magnesium sulfate heptahydrate or to any of the excipients.

2. Hepatic encephalopathy, hepatic failure or renal failure.

3. Parenteral magnesium salts should generally be avoided in patients suffering from heart block.

Adverse Reactions:

1. In patients with impaired renal function there may be sufficient accumulation to produce toxic effects.

2. Excessive administration of magnesium leads to the development of hypermagnesaemia. Symptoms of hypermagnesaemia may include nausea, vomiting, flushing of the skin, thirst, hypotension due to peripheral vasodilatation, drowsiness, confusion, loss of tendon reflexes and respiratory depression due to neuromuscular blockade, muscle weakness, respiratory depression, cardiac arrhythmias, coma, and cardiac arrest.

3. Metabolism and nutrition disorders

4. Electrolyte/fluid abnormalities (hypophosphataemia, hypertonic dehydration)

5. Hypersensitivity reactions.

6. Hypocalcaemia: There have been isolated reports of maternal and fetal hypocalcaemia with high doses of magnesium sulfate.

Drug interactions:

1. Muscle Relaxants: non-depolarising muscle relaxants such as tubocurarine are enhanced by parenteral magnesium salts.

2. Calcium channel blockers such as nifedipine or nimodipine may rarely lead to a calcium ion imbalance and could result in abnormal muscle function. Nifedipine: profound hypotension was produced in two women who were given oral Nifedipine.

Magnesium salts should also be administered with caution to those receiving digitalis glycosides. Parenteral administration of magnesium salts may enhance the effects of neuromuscular blocking agents or of central nervous system depressants.

3. CNS Depressants: When barbiturates, opiates, general anaesthetics, or other CNS depressants are administered concomitantly with magnesium sulfate, dosage of these agents must be carefully adjusted because of the additive central depressant effects.

Antibacterials: The neuromuscular blocking effects of parenteral magnesium and aminoglycoside antibacterials may be additive.

Storage instructions:

Do not store above30° C.