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Magnesium Sulfate 20% w/v Solution for Injection or Infusion

⚠ This medicine appears to have been discontinued

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.

Active substance: Magnesium sulfate heptahydrate

Source: electronic medicines compendium (emc)
Official leaflet: Read the PIL on emc

What it is and what it is used for

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:

  • treat low levels of magnesium in the blood
  • prevent and control further seizures (fits) in patients with eclampsia (fits during pregnancy)
  • prevent and control seizures (fits) in severe pre-eclampsia (high blood pressure associated with pregnancy).

What you need to know before you take it

e Magnesium Sulfate Solution for Injection or Infusion Do not use Magnesium Sulfate Solution for Injection or Infusion if you:

  • are allergic to magnesium sulfate or any other ingredients of this medicine (listed in section 6)
  • have or had kidney failure
  • have or had liver problems and failure
  • have or had heart problems Talk to your doctor if you are concerned about any of the above. Warnings and Precautions Talk to your doctor, pharmacist or nurse before being given Magnesium Sulfate Solution for Injection or Infusion if you:
  • have or had liver disease or have kidney disease as your doctor may need to adjust your dose
  • have any breathing difficulties or lung diseases
  • have a disease causing muscle weakness and fatigue (myasthenia gravis) Children and adolescents There is no relevant use of Magnesium Sulfate Solution for Injection or Infusion in children for the treatment of hypomagnesaemia. Magnesium sulfate can be used with caution in female adolescents with pre-eclampsia and eclampsia. Other medicines and Magnesium Sulfate Solution for Injection or Infusion Tell your doctor, pharmacist or nurse if you are using, have recently used or might use any other medicines. This includes medicines bought without a prescription, including herbal medicines. In particular, tell your doctor if you are using any of the following medicines:
  • Muscle relaxants, for example rocuronium or vecuronium
  • Calcium-channel blockers, e.g. nifedipine, lercanidipine or amlodipine, may result in abnormal muscle function and low blood pressure
  • Central nervous system depressants (medicines which act on the brain to cause drowsiness), such as drugs used in anxiety called benzodiazepines (e.g. diazepam) or medicines to help with sleeping called hypnotics (e.g. zopiclone)
  • Aminoglycoside antibacterial (used to treat infections), for example gentamicin and tobramycin
  • Heart medicines such as digitalis glycosides and digoxin
  • Intravenously administered calcium
  • Diuretic agents e.g. furosemide
  • Antacids and laxatives
  • Vasodilator agents such as non-selective alpha-adrenergic blockers e.g. phentolamine
  • Cisplatin, amphotericin B and ciclosporin. Pregnancy, breast-feeding and fertility If you are pregnant or breast-feeding, think you may be pregnant or are planning to have a baby, ask your doctor, pharmacist or nurse for advice before using this medicine. Tell your doctor if you are pregnant or trying to become pregnant. Magnesium Sulfate Solution for Injection or Infusion is used to treat serious complications in pregnancy. Your doctor will only give you Magnesium Sulfate Solution for Injection or Infusion if the benefit of treatment outweighs the risk to you and the developing baby. Low blood calcium levels and effects on the bones, such as reduced bone density, have been reported in babies whose mothers were given magnesium sulfate continuously for more than 5-7 days during pregnancy. If used repeatedly or for longer periods during pregnancy, monitoring of mineral levels and skeletal side effects in the newborn baby should be considered. Driving and using machines Do not drive or operate machines if you feel dizzy, tired, sleepy, have vertigo or blurred vision after taking this medicine.

How to take it

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:

  • Hypersensitivity, for example an itchy rash, swelling of the hands, feet, ankles, face, lips, mouth or throat (which may cause difficulty in swallowing or breathing) or a feeling that you are going to faint. Excessive administration of magnesium leads to the development of symptoms of hypermagnesaemia. This can include the side effects as listed below. Serious side effects which are very rare are:
  • heart attack (shortness of breath, chest pain, feeling faint and/or dizzy)
  • coma
  • hypermagnesaemia The other side effects are:
  • problems with the balance of salts and water in the blood. This may lead to thirst (which may be severe)
  • flushing of the skin
  • tiredness
  • skin rashes
  • loss of knee jerk reflex
  • muscle weakness
  • abnormal heartbeats
  • shallow or slow breathing
  • feeling or being sick
  • sweating
  • high temperature
  • headache, dizziness, confusion
  • double vision, blurred vision and drooping eyelid
  • slurred speech
  • pain, burning, inflammation and bruising at injection site There have been isolated reports of low blood calcium levels in mothers and their newborn babies following prolonged use and high doses of magnesium sulfate during pregnancy. Reporting of Side Effects If you get any side effects, talk to your doctor, pharmacist or nurse. This includes any possible

Possible side effects

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.

How to store it

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.

Contents of the pack and other information

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

Frequently asked questions about Magnesium Sulfate 20% w/v Solution for Injection or Infusion

How do I take Magnesium Sulfate 20% w/v Solution for Injection or Infusion?

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.

What is the active substance in Magnesium Sulfate 20% w/v Solution for Injection or Infusion?

The active substance in Magnesium Sulfate 20% w/v Solution for Injection or Infusion is magnesium sulfate heptahydrate.

Are there equivalent medicines to Magnesium Sulfate 20% w/v Solution for Injection or Infusion?

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.

Where does this information come from?

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.

Can I get Magnesium Sulfate 20% w/v Solution for Injection or Infusion without a prescription?

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.

About this leaflet

The text above reproduces the patient information leaflet approved for this medicine, restructured for easier reading.

Medical disclaimer: This page is for information only and does not replace advice from your doctor or pharmacist. Always read the leaflet supplied with your medicine. If you are unwell, call NHS 111; in an emergency, call 999.

Medicines with the same active substance: Magnesium sulfate heptahydrate (10 medicines)
See every medicine containing this substance, or browse the full A–Z of active substances.
⚕For healthcare professionals — Summary of Product Characteristics (SmPC)Full SmPC: dosage, interactions, contraindications, warnings+
Technical information intended for healthcare professionals (doctors and pharmacists). The Summary of Product Characteristics (SmPC) is the official document approved by the MHRA/EMA. It does not replace the patient leaflet or a doctor’s advice.

4.1. 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.

4.2. 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). 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.

4.3. Contraindications

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.

4.4. Special warnings and precautions for use

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.

4.5. Interaction with other medicinal products and other forms of interaction

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.

4.6. Fertility, pregnancy and lactation

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.

4.7. Effects on ability to drive and use machines

Not relevant

4.8. Undesirable effects

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.

4.9. Overdose

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 about this leaflet

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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