Patient leaflets and SmPCs, drug interaction checker, official dosages and NHS pharmacy opening hours — all in one place.
Patient leaflets and SmPCs, drug interaction checker, official dosages and NHS pharmacy opening hours — all in one place.
The electronic medicines compendium (emc) no longer publishes a Summary of Product Characteristics for this product, which usually means it is no longer marketed in the UK. The patient leaflet below is kept for reference, but the product may not be available.
If you were prescribed this medicine, other products containing Magnesium sulfate heptahydrate may still be available. Do not stop your treatment — ask your pharmacist or GP what to use instead.
for The name of your medicine is Magnesium Sulfate 20% w/v Solution for Injection or Infusion. This will be referred to as Magnesium Sulfate Solution for Injection or Infusion throughout this leaflet. This medicine is an electrolyte solution and contains the active substance, magnesium sulfate heptahydrate, which plays a number of important roles in the body, including regulation of the nervous and blood systems. Magnesium Sulfate Solution for Injection or Infusion is used to:
e Magnesium Sulfate Solution for Injection or Infusion Do not use Magnesium Sulfate Solution for Injection or Infusion if you:
Magnesium Sulfate Solution for Injection or Infusion Your doctor will decide what dose of this medicine you should be given. Check with your doctor, pharmacist or nurse if you are not sure. The dose will depend on the individual needs and the response to treatment. Your blood levels will be monitored during treatment. Treatment of magnesium deficiency The recommended dose for the treatment of magnesium deficiency is up to 200 mL of a 20% w/v solution by slow intravenous infusion given over a period of up to 5 days. Prevention and control of seizures in severe pre-eclampsia The recommended dose is an initial dose of 20 mL of a 20% w/v solution given slowly over a period of 5-15 minutes, followed by an infusion of 5 mL of a 20% w/v solution per hour for 24 hours after the last seizure.
Information for healthcare professionals only (as stated on the Summary of Product Characteristics) The following information is intended for healthcare professionals only: Therapeutic indications Treatment of magnesium deficiency in hypomagnesaemia. Prevention and control of seizures in severe pre-eclampsia. Prevention and control of recurrent seizures in eclampsia. Posology and Method of Administration Posology Dosages should be adjusted according to the patient's needs, responses and weight. Plasma magnesium levels should also be monitored during treatment to determine the rate and duration of infusion. Close monitoring for ECG changes is required (see section 4.8 of the SmPC). The infusion rate should be reduced or stopped if the patient develops signs of changes to cardiac condition (ECG changes). Treatment of magnesium deficiency in hypomagnesaemia: Treatment should be given via an infusion pump and an infusion rate of 1 g magnesium sulfate (5 mL of a 20% w/v solution equivalent to 4mmol of magnesium ions) per hour is recommended, with a maximum rate of 2 g magnesium sulfate (10 mL of a 20% w/v solution approximately 8 mmol magnesium ions) per hour (not exceeding 28 g in 24 hours). Higher infusion rates may be given in the management of emergencies. Up to 40 g (200 mL of a 20% w/v solution equivalent to 160 mmol of magnesium ions) by slow intravenous infusion (in glucose 5% w/v) given over a period of up to 5 days, may be required to replace the deficit (allowing for urinary losses). In exceptional circumstances and under close supervision a higher dose within the range of 2 g to 5 g of magnesium sulfate (10 mL to 25 mL of a 20% w/v solution equivalent to 8 to 20 mmol of magnesium ions) in at least 100 mL of Glucose 5% w/v or Sodium Chloride 0.9% w/v over 6 hours may be considered. Prevention and control of seizures in severe pre-eclampsia: An intravenous loading dose of typically 4 g (20 mL of a 20% w/v solution equivalent to 16 mmol of magnesium ions) given slowly over a period of 5-15 minutes is followed by an infusion of 1 g (5 mL of a 20% w/v solution equivalent to 4 mmol of magnesium ions) per hour for 24 hours after the last seizure. Prevention and control of recurrent seizures in eclampsia: An intravenous loading dose of typically 4 g (20 mL of a 20% w/v solution equivalent to 16 mmol of magnesium ions) given slowly over a period of 5-15 minutes is followed by an infusion of 1 g (5 mL of a 20% w/v solution equivalent to 4 mmol of magnesium ions) per hour continued for 24 hours after the last seizure or delivery postpartum (whichever is later). continued overleaf
Prevention and control of further seizures in eclampsia The recommended dose is an initial dose of 20 mL of a 20% w/v solution given slowly over a period of 5-15 minutes, followed by an infusion of 5 mL of a 20% w/v solution per hour, continued for 24 hours after the last seizure. If seizures recur, a further 10-20 mL of magnesium can be given over 5 minutes via IV route. You may be given a different dose by your doctor if you have problems with your kidneys or liver. If more of Magnesium Sulfate Solution for Injection or Infusion is given than should be As this medicine is being given by your doctor or nurse, it is unlikely that you will be given too much of this medicine, however, tell your doctor as soon as possible if you have any concerns. In the unlikely event of an overdose your doctor will monitor your side effects. If you are a medical practitioner administering this medicine an overdose may be reversed with calcium salts which should be administered slowly intravenously in a dose equivalent to 2.5 to 5 mmol of calcium (please refer to the Summary of Product Characteristics). If you have any further questions on the use of this medicine, ask your doctor, pharmacist or nurse.
4. Possible side effects Like all medicines, this medicine can cause side effects, although not everybody gets them. The following side effects have been observed with the use of magnesium sulfate:
not listed in this leaflet. You can also report side effects directly via the Yellow Card Scheme at: www.mhra.gov.uk/yellowcard or search for MHRA Yellow Card in the Google Play or Apple APP Store. By reporting side effects, you can help provide more information on the safety of this medicine.
Magnesium Sulfate Solution for Injection or Infusion Keep this medicine out of the sight and reach of children. Do not use this medicine after the expiry date which is stated on the vial and carton. The expiry date refers to the last day of the month. This medicine does not require any special storage conditions. This medicine must be used immediately after opening of the container and the storage of open vials avoided. Do not throw away any medicines via wastewater or household waste. Ask your pharmacist how to throw away medicines you no longer use. These measures will help protect the environment.
What Magnesium Sulfate Solution for Injection or Infusion contains The active substance is magnesium sulfate heptahydrate at a strength of 200 g per litre (approximately 0.8 mmol magnesium per mL). The other ingredients are sulfuric acid and Water for Injections. What Magnesium Sulfate Solution for Injection or Infusion looks like and contents of the pack This medicine is a clear and colourless solution. This medicine is available in 20 mL and 50 mL vials, packed into cartons containing 1 vial or 10 vials. Not all pack sizes may be marketed. Marketing Authorisation Holder and Manufacturer Torbay Pharmaceuticals Limited, Wilkins Drive, Paignton, Devon, TQ4 7FG, UK +44 (1803) 664707 [email protected] This leaflet was last revised in: October 2024 PL 56021/0015
PIL/15/3
continued from overleaf If seizures recur, a further 2-4 g (10-20 mL of a 20% w/v solution equivalent to 8-16 mmol of magnesium ions), depending on the woman's weight, 2 g (8 mmol) if less than 70 kg, is given intravenously over 5 minutes. Renal impairment Appropriate reductions in dosage should be made for patients with renal impairment due to increased risk of toxicity (see section 4.4 of the SmPC). Caution must be observed to prevent exceeding the renal capacity. The dosage should not exceed 20 g in 48 hours (100 mL of a 20% w/v Solution equivalent to 80 mmol of magnesium ions). Elderly There are no special recommendations for use in the elderly but caution needs to be exercised in this population due to the risk of renal impairment (see section 4.4. of the SmPC). Paediatric Population There is no relevant use of Magnesium Sulfate 20% w/v Solution for Injection or Infusion in the paediatric population for the indication of hypomagnesaemia. Limited studies of the use of the magnesium sulfate in adolescent females with pre-eclampsia and eclampsia show there are no contraindications, however it should be used with caution. Method of administration For intravenous administration. For peripheral administration a concentration of magnesium sulfate 5% w/v (diluted with Glucose 5% w/v or Sodium Chloride 0.9% w/v) is recommended. For example, dilute 25 mL of Magnesium Sulfate 20% w/v to 100 mL using Glucose 5% w/v or Sodium Chloride 0.9% w/v. The resultant admixture contains 20 mmol (5g) of magnesium ions per 100 mL. For instructions on dilution of the medicinal product before administration see section 6.6 of the SmPC. Incompatibilities This medicinal product must not be mixed with other medicinal products, with the exception of dilution with Glucose 5% w/v or Sodium Chloride 0.9% w/v solutions. Shelf life 36 months Chemical and physical in use-stability has been demonstrated for 24 hours at a maximum of 25°C. From a microbiological point of view, the product should be used immediately. If not used immediately, in use storage times and conditions prior to use are the responsibility of the user and would normally not be longer than 24 hours at 2-8°C, unless dilution has taken place in controlled and validated aseptic conditions. PIL/15/3
Magnesium Sulfate 20% w/v Solution for Injection or Infusion comes as injection. Always follow the dose your doctor or pharmacist has given you, and read the leaflet that comes with the medicine.
The active substance in Magnesium Sulfate 20% w/v Solution for Injection or Infusion is magnesium sulfate heptahydrate.
Medicines with the same active substance, strength and form include: Magnesium Sulfate 10% w/v Solution for Injection/Infusion, Magnesium Sulfate 50% w/v Solution for Injection/Infusion. They are interchangeable only if your prescriber or pharmacist says so.
This leaflet reproduces the patient information leaflet approved for Magnesium Sulfate 20% w/v Solution for Injection or Infusion, as published on the electronic medicines compendium (emc). The version printed inside your medicine’s packaging is the one that applies to you.
Whether a medicine is available over the counter or on prescription only depends on its licence. Check the leaflet, or ask your pharmacist — they can tell you straight away.
The text above reproduces the patient information leaflet approved for this medicine, restructured for easier reading.
Treatment of magnesium deficiency in hypomagnesaemia.
Prevention and control of seizures in severe pre-eclampsia.
Prevention and control of recurrent seizures in eclampsia.
Posology
Dosages should be adjusted according to the patient's needs, responses and weight. Plasma magnesium levels should also be monitored during treatment to determine the rate and duration of infusion.
Close monitoring for ECG changes is required (see section 4.8). The infusion rate should be reduced or stopped if the patient develops signs of changes to cardiac condition (ECG changes).
Treatment of magnesium deficiency in hypomagnesaemia:
Treatment should be given via an infusion pump and an infusion rate of 1 g magnesium sulfate (5 mL of a 20% w/v solution equivalent to 4 mmol of magnesium ions) per hour is recommended, with a maximum rate of 2 g magnesium sulfate (10 mL of a 20% w/v solution approximately 8 mmol magnesium ions) per hour (not exceeding 28 g in 24 hours).
Higher infusion rates may be given in the management of emergencies. Up to 40 g (200 mL of a 20% w/v solution equivalent to 160 mmol of magnesium ions) by slow intravenous infusion (in glucose 5% w/v) given over a period of up to 5 days, may be required to replace the deficit (allowing for urinary losses).
In exceptional circumstances and under close supervision a higher dose within the range of 2 g to 5 g of magnesium sulfate (10 mL to 25 mL of a 20% w/v solution equivalent to 8 to 20 mmol of magnesium ions) in at least 100 mL of Glucose 5% w/v or Sodium Chloride 0.9% w/v over 6 hours may be considered.
Prevention and control of seizures in severe pre-eclampsia:
An intravenous loading dose of typically 4 g (20 mL of a 20% w/v solution equivalent to 16 mmol of magnesium ions) given slowly over a period of 5-15 minutes is followed by an infusion of 1 g (5 mL of a 20% w/v solution equivalent to 4 mmol of magnesium ions) per hour for 24 hours after the last seizure.
Prevention and control of recurrent seizures in eclampsia:
An intravenous loading dose of typically 4 g (20 mL of a 20% w/v solution equivalent to 16 mmol of magnesium ions) given slowly over a period of 5-15 minutes is followed by an infusion of 1 g (5 mL of a 20% w/v solution equivalent to 4 mmol of magnesium ions) per hour continued for 24 hours after the last seizure or delivery postpartum (whichever is later).
If seizures recur, a further 2-4 g (10-20 mL of a 20% w/v solution equivalent to 8-16 mmol of magnesium ions), depending on the woman's weight, 2 g (8 mmol) if less than 70 kg, is given intravenously over 5 minutes.
Renal impairment
Appropriate reductions in dosage should be made for patients with renal impairment due to increased risk of toxicity (see section 4.4). Caution must be observed to prevent exceeding the renal capacity. The dosage should not exceed 20 g in 48 hours (100 mL of a 20% w/v Solution equivalent to 80 mmol of magnesium ions).
Elderly
There are no special recommendations for use in the elderly but caution needs to be exercised in this population due to the risk of renal impairment (see section 4.4).
Paediatric Population
There is no relevant use of Magnesium Sulfate 20% w/v Solution for Injection or Infusion in the paediatric population for the indication of hypomagnesaemia.
Limited studies of the use of the magnesium sulfate in adolescent females with pre- eclampsia and eclampsia show there are no contraindications, however it should be used with caution.
Method of administration
For intravenous administration.
For peripheral administration a concentration of magnesium sulfate 5% w/v (diluted with Glucose 5% w/v or Sodium Chloride 0.9% w/v) is recommended. For example, dilute 25 mL of Magnesium Sulfate 20% w/v to 100 mL using Glucose 5% w/v or Sodium Chloride 0.9% w/v. The resultant admixture contains 20 mmol (5 g) of magnesium ions per 100 mL.
For instructions on dilution of the medicinal product before administration, see section 6.6.
Hypersensitivity to the active substance or any of the excipients listed in section 6.1. Severe renal failure.
Hepatic encephalopathy, hepatic failure.
Parenteral magnesium salts should generally be avoided in patients with a heart block.
Concentrations of more than 5% w/v magnesium sulfate have a high osmolarity and may cause venous irritation and tissue damage in cases of extravasation, monitor the insertion site closely.
Magnesium salts are excreted mainly by the kidney and should be administered with caution to patients with impaired renal function and appropriate dosage reduction should be made due to the risk of hypermagnesaemia (See section 4.2).
Due to the risk of respiratory depression as a result of hypermagnesaemia, patients should be closely monitored for signs and symptoms of magnesium toxicity. In particular, caution is required in patients with respiratory disease.
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 the individual cases prior to initiation of treatment.
Serum calcium levels should be routinely monitored in patients receiving magnesium sulfate. Maternal administration of magnesium sulfate for longer than 5–7 days in pregnancy has been associated with skeletal adverse effects and hypocalcaemia and hypermagnesaemia in neonates. If use of magnesium sulfate in pregnancy is prolonged or repeated, consider monitoring of neonates for abnormal calcium and magnesium levels and skeletal adverse effects.
Muscle relaxants
Non-depolarising neuromuscular blocking drugs, such as rocuronium or vecuronium muscle relaxants are enhanced by parenteral magnesium salts.
Cardiac glycosides
Magnesium salts should also be administered with caution to those patients receiving digitalis glycosides and digoxin.
Electrolyte imbalance
Diuretic agents (e.g. furosemide), antacids and laxatives may lead to an electrolyte imbalance and has been associated with an increase in cardiopulmonary events.
Vasodilators
Magnesium causes vasodilation and therefore vasodilator agents such as non- selective alpha-adrenergic blockers (e.g. phentolamine) may be enhanced.
Calcium channel blockers
Concomitant use of calcium- channel blockers, such as nifedipine or amlodipine may rarely lead to calcium ion imbalance and could result in abnormal muscle function.
Magnesium sulfate potentially increases the risk of hypotension when given concomitantly with oral calcium ion channel blockers such as nifedipine, lercanidipine and amlodipine. Profound hypotension was produced in two women who were given oral nifedipine.
CNS depressants
Parenteral administration of magnesium sulfate may enhance the effects of central nervous system depressants. The neuromuscular blocking effects of parenteral magnesium and aminoglycoside antibacterials may be additive. When 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.
Other drugs
Certain drugs, such as Cisplatin, amphotericin B and ciclosporin, have been associated with magnesium wasting, increasing the risk of acute hypomagnesaemia due to inadequate absorption.
Intravenous calcium will antagonise the effects of magnesium.
Pregnancy
As eclampsia may be life threatening to mother and baby, magnesium sulfate may be administered for this condition.
Magnesium crosses the placenta and may produce hypotonia, hypoflexia and hypotension. If administered during labour it may cause respiratory depression of the newborn infant.
Magnesium sulfate can cause skeletal adverse effects when administered continuously for more than 5-7 days in pregnant women. There are retrospective epidemiological studies and case reports documenting foetal adverse effects including hypocalcaemia, skeletal demineralisation, osteopenia and other skeletal adverse effects with maternal administration of magnesium sulfate for more than 5 -7 days. The clinical significance of the observed effects is unknown.
If prolonged or repeated exposure to magnesium sulfate occurs during pregnancy monitoring of neonates for abnormal calcium or magnesium levels and skeletal adverse effects should be considered.
Breast-feeding
There is evidence that an increased level of magnesium is present in breast milk following treatment with magnesium sulfate. Safety during breast feeding has not been established. Therefore, as with all drugs, it is not advisable to administer magnesium sulfate during breast feeding unless considered essential.
Fertility
The long-term experience reports no effects of magnesium sulfate on fertility. However, there are no controlled studies on the effects of magnesium sulfate on fertility.
Not relevant
Summary of Safety Profile
Commonly reported adverse reactions include flushing, nausea and vomiting, thirst, muscle weakness. The most important serious adverse reactions associated with magnesium sulfate relate to hypermagnesaemia. These include respiratory depression leading to cardiac arrest.
Tabulated Summary of Adverse Reactions
Adverse reactions associated with intravenous magnesium sulfate from clinical studies and case reports are tabulated below. The table is presented in order of system organ class.
System Organ Class
Adverse reaction
Immune system disorders
Hypersensitivity reactions
Metabolic and nutritional disorders
Hypophosphataemia, hyperosmolar dehydration, hypocalcaemia, hypermagnesaemia, hypoglycaemia
Nervous system disorders
Headache, dizziness, slurred speech, drowsiness and confusion, coma
Eye disorders
Visual disturbances including diplopia ptosis or abnormal vision
Cardiac disorders
ECG changes (prolonged PR, QRS and QT intervals), bradycardia, tachycardia, cardiac arrythmias, cardiac arrest
Vascular disorders
Flushing, peripheral vasodilation leading to hypotension
Respiratory, thoracic and mediastinal disorders
Dyspnoea, pulmonary oedema, respiratory depression, respiratory arrest
Gastrointestinal disorders
Nausea, vomiting, thirst
Skin and subcutaneous tissue disorders
Urticaria
Musculoskeletal and connective tissue disorders
Loss of tendon reflexes due to neuromuscular blockade, muscle weakness
General disorders and administration site conditions
Pain, burning, inflammation and bruising at injection site
There have been isolated reports of maternal and foetal hypocalcaemia with high doses of magnesium sulfate.
Especially in patients with impaired renal function, there may be sufficient accumulation of magnesium sulfate to produce toxic effects.
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. Healthcare professionals are asked to report any suspected adverse reactions via the Yellow Card Scheme at: www.mhra.gov.uk/yellowcard or search for MHRA Yellow Card in the Google Play or Apple App Store.
Signs
Clinical signs of overdose will be those of hypermagnesaemia, including nausea, vomiting, flushing, thirst, hypotension, drowsiness, confusion, absence of reflexes, respiratory depression, slurred speech, diplopia, muscle weakness, arrythmias, coma and cardiac arrest.
Treatment
Appropriate action should be taken to reduce the blood level of magnesium to avoid hypermagnesaemia. Neuromuscular blockade associated with hypermagnesaemia may be reversed with calcium salts such as calcium gluconate, which should be administered intravenously in a dose equivalent to 2.5 to 5 mmol of calcium.
Ask anything about Magnesium Sulfate 20% w/v Solution for Injection or Infusion. The assistant answers only from this leaflet — if the leaflet does not cover it, it will say so. It does not give medical advice.
Answers come from the patient leaflet published on the electronic medicines compendium (emc). They are not medical advice. Ask a pharmacist or your GP if you are unsure. For urgent help call NHS 111, or 999 in an emergency.
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