MAGNESIUM SULFATE

4). Posology Dosage should be tailored according to the individual’s needs and responses and should be reduced in renal impairment. Plasma magnesium concentrations should be measured to determine the rate and duration of infusion and should be monitored throughout therapy.

1 mL <Magnesium sulfate> 50% w/v contains 500 mg magnesium sulfate heptahydrate corresponding to approximately 2 mmol (49 mg = 4 mEq) magnesium ions. 1 mmol Mg2+. For the intravenous route, the 50% w/v solution requires dilution to a concentration of not more than 20%.

For instructions on dilution of <Magnesium sulfate> 50% w/v to a 20% w/v solution see section “Method of administration”.

Posology Treatment of magnesium deficiency in proven hypomagnesaemia Adults:

Intravenous route: intravenous infusion Up to 80 mL Magnesium sulfate 50% w/v solution diluted in an infusion solution should be administered by slow intravenous infusion over a period of up to five days and titrated to clinical need.

The usual regimen is 16 – 24 mL Magnesium sulfate 50% w/v solution diluted in an infusion solution in the first 24 hours followed by 8 – 12 mL Magnesium sulfate 50% w/v solution diluted in an infusion solution per day for 3 or 4 days, administered by intravenous infusion.

Intramuscular route: 2 – 4 mL Magnesium sulfate 50% w/v solution undiluted or diluted (4 – 8 mL of a 25% w/v solution) can be given intramuscularly every 6 hours for 24 hours (a total of 4 doses). 5 mL/kg bw of a 20% w/v solution) every 6 – 12 hours as required, to be given by intravenous injection over at least 10 minutes.

25 mL/kg bw of a 20% w/v solution) every 12 hours as required, to be given by intravenous injection over at least 10 minutes. Adolescent 12 – 17 years 2 mL Magnesium sulfate 50% w/v solution diluted (5 mL of a 20% w/v solution) every 12 hours as required, to be given by intravenous injection over at least 10 minutes.

Prevention of hypomagnesaemia in patients receiving total parenteral nutrition Adults: Intravenous route: intravenous infusion 5 – 10 mL Magnesium sulfate 50% w/v solution daily, diluted in an infusion solution, usual dose 6 mL Magnesium sulfate 50% w/v solution daily, diluted in an infusion solution, to be given by intravenous infusion.

The frequency of undesirable effects is not known.

Immune system disorder:

Hypersensitivity reactions. Excessive administration of magnesium leads to the development of symptoms of hypermagnesaemia which may include: Metabolism and nutrition disorders Electrolyte/fluid abnormalities (hypophosphataemia, hypertonic dehydration) There have been isolated reports of maternal and fetal hypocalcaemia with high doses of magnesium sulfate.

Nervous system disorders Respiratory depression Nausea, vomiting, drowsiness and confusion Coma Slurred speech, double vision Loss of tendon reflexes due to neuromuscular blockade Cardiac disorders Cardiac arrhythmias, cardiac arrest ECG abnormal (prolonged PR, QRS and QT intervals), bradycardia Vascular disorders Flushing of the skin and hypotension due to peripheral vasodilatation Musculoskeletal and connective tissue disorders Muscle weakness General disorders and administration site conditions Thirst Especially in patients with impaired renal function, there may be sufficient accumulation of magnesium sulfate to produce toxic effects.

Injection/infusion-related Too rapid administration:

Vasodilatation, reduced blood pressure Local: may be irritant to veins; extravasation may cause tissue damage Intramuscular: pain, redness, swelling or warmth at the injection site, drainage at the injection site, prolonged bleeding, cellulitis, sterile abscess, signs of an allergic reaction, such as difficulty breathing or facial swelling, injury to nearby structures (blood vessels, bones, or nerves), inadvertent intravascular or intra-ostial injection, tissue necrosis, poor absorption due to high injectate volume.

Reporting of suspected adverse reactions Reporting suspected adverse reactions after authorisation of the medicinal product is important. It allows continued monitoring of the benefit/risk balance of the medicinal product. uk/yellowcard or search for MHRA Yellow Card in the Google Play or Apple App Store.

Magnesium salts should be administered with caution to patients with impaired renal function and appropriate dosage reduction should be made. Serum calcium levels should be routinely monitored in patients receiving magnesium sulfate.

0 mmol). Monitoring of the absence of respiratory depression: the breath rate should not be under 16 breaths/min. 3). The presence of the patellar reflex should be checked. Administer with caution if flushing and sweating occurs. An antidote of injectable calcium gluconate solution should be immediately available.

2). The 50% w/v solution MUST be diluted before use for IV administration; concentrations up to 20% w/v are usually employed. For IM use, a 25% w/v or 50% w/v solution is acceptable. For the intramuscular route, use good clinical practice for intramuscular injections.

The 50% w/v solution should be used undiluted or diluted to 25% w/v. Avoid muscles which are emaciated or atrophied. Avoid the dorsogluteal muscle and sciatic nerve. If the total dose to be administered exceeds 5 mL, the injection volume should be divided between more than one deep muscular injection site.

Use caution in older or thin patients who may only tolerate up to 2 mL in a single injection. Do not use an injection site that has evidence of infection or injury. If repeating an intramuscular dose, rotate injection sites to avoid injury or discomfort to the muscles.

1. Hepatic encephalopathy, hepatic failure, renal failure. Severe renal impairment (glomerular filtration rate under 30 mL/h), anuria. Parenteral administration of the medicinal product is contraindicated in patients with heart block (class I-III) or myocardial damage and myasthenia gravis.