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Active substance: MAGNESIUM SULPHATE

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Patient Information Leaflet: Magnesium Sulphate 50% w/v Solution for Injection
Magnesium Sulphate BP

1. What Magnesium Sulphate Injection
is for
Read all of this leaflet carefully before you
are given this medicine.
• Keep this leaflet. You may need to read it
• If you have any further questions, ask
your doctor or nurse.
• In this leaflet, Magnesium Sulphate 50%
w/v Solution for Injection will be called
Magnesium Sulphate Injection.
In this leaflet:
1. What Magnesium Sulphate Injection is
2. Before you are given Magnesium
Sulphate Injection
3. How you will be given Magnesium
Sulphate Injection
4. Possible side effects
5. How to store Magnesium Sulphate
6. Further information.

Magnesium Sulphate belongs to a group of
medicines called mineral supplements.
Magnesium is important for many systems
in the body, especially the muscles and nerves.
Magnesium Sulphate Injection is given to
increase the amount of magnesium in the
body where the blood levels of magnesium
are lower than normal (hypomagnesaemia),
and where it is not possible for the medicine
to be taken by mouth. This can be due to
problems with absorption of magnesium,
severe diarrhoea, chronic alcoholism,
malnutrition or having to have all nutrients
by injection.

2. Before you are given Magnesium
Sulphate Injection
You should not be given Magnesium
Sulphate Injection if:
• You are allergic to the active ingredient,
magnesium sulphate
• You are allergic to the other ingredients
of Magnesium Sulphate Injection (see
section 6.)
• You are suffering from any form of heart
disease, for example, you have had a
heart attack of heart block (where your
heart beat signals are delayed)
• You have kidney failure.
If the above applies to you talk to your
doctor or nurse.

Check with your doctor before being given
Magnesium Sulphate Injection if:

If any of the above applies to you talk to
your doctor or nurse.

• You are pregnant, planning to become
pregnant or breast-feeding
• You have kidney problems.
• You have myasthenia gravis (a condition
causing muscle weakness)
Magnesium sulphate injection will not be
given to you if you are in a coma resulting
from liver problems if there is a risk of
kidney failure.
Tell your doctor if you are taking any of
the following medicines:
• Medicines for heart disease called cardiac
glycosides (such as digoxin, digitoxin)
• Muscle relaxants, used during
anaesthesia, as using these medicines
with Magnesium Sulphate may cause
their effect to be increased
• Medicines called opioids (such as
morphine), barbiturates (such as
amylobarbitone) or hypnotics (such as
nitrazepam), as using these medicines
with Magnesium Sulphate can cause
slow and/or shallow breathing
• Nifedipine or nimodipine, which may be
used to treat high blood pressure or
angina, as using this medicine with
Magnesium Sulphate can cause problems
with muscle function
• Aminoglycoside antibacterials (such as
• Any other medicine, including medicines
obtained without a prescription.

Pregnancy and breast-feeding
If you are pregnant, trying to become
pregnant or are breast-feeding, ask your
doctor or nurse for advice before being
given Magnesium Sulphate.
Driving and using machines
Magnesium Sulphate may cause
drowsiness. If this happens to you, do not
drive or use machinery.

3. How you will be given Magnesium
Sulphate Injection
Magnesium Sulphate Injection will be given
to you by your doctor or nurse.
Your doctor will choose the dose that is
right for you.
You will be given Magnesium Sulphate
Injection by your doctor or nurse as an
injection into a muscle or, after dilution,
into a vein, depending on your condition
and how much your body needs.
For injection into a vein, the solution
should be diluted to 20% or less, and the
rate of injection should be less than 1.5 ml
per minute of a 10% solution.
Adults and the Elderly
• Treatment of mild magnesium deficiency:
- 1 gram (g) every 6 hours for 4 doses,
injected into a muscle.

• Treatment of severe magnesium deficiency:
- Up to 250 milligrams (mg) per kilogram
(kg) of body weight injected into a muscle
over 4 hours or 5 g per litre of infusion
solution given intravenously over 3 hours
• The solution should be diluted to 20% if
being injected into a muscle.
• If it is injected into a vein the solution should
be diluted to 1% and given over 1 hour.
• In severe conditions half the dose may be
given in the first 15 - 20 minutes.
• Up to a 3% solution may be used in sever
• The usual dose for babies is 25 - 50 mg per
kg every 8 to 12 hours for 2 to 3 doses
• The usual dose for children is 25 - 50 mg
per kg every 4 to 6 hours for 3 to 4 doses.
Patients with kidney problems
Your doctor may give you a lower dose.
Medical check-ups
While you are receiving this medicine, your
doctor will want you to have regular blood
tests to check your condition. This is to make
sure that your medicine is working properly and
that the dose you are receiving is right for you.
If you are given more Magnesium Sulphate
Injection than you should
If you think you have been given too much
Magnesium Sulphate Injection you should tell
your doctor.
Too much Magnesium Sulphate can lead to
raised levels of magnesium in the blood

(hypermagnaesemia), with symptoms of flushing,
feel thirsty, low blood pressure, drowsiness,
feeling or being sick, confusion, slurred speech,
double vision, loss of knee jerk reflex, muscle
weakness, slow and/or shallow breathing and
irregular heart beat. If treatment is not
stopped or attempts not made to lower the
blood levels of magnesium, this could
eventually lead to coma or heart attack. You
may be given an injection of a calcium salt to
help to lower very high levels of magnesium.
If you have any further questions about the use
of this medicine, ask your doctor or nurse.

4. Possible side effects
Like all medicines Magnesium Sulphate
Injection can cause side effects, although not
everybody gets them.
Seek immediate medical help if you have an
allergic reaction. This includes any of the
following symptoms:
• Difficulties in breathing
• Swelling of your eyelids, face or lips
• Rash or itching especially those covering
your whole body
Other side effects:
Effects on the heart and blood
• Low blood pressure
• Irregular or slow heart beat
• Heart attack
• low levels of Calcium in your blood. (This
may cause you to have pins & needles or
twitching muscles)

Effects on respiration
• Slow and/or shallow breathing
Effects on the stomach and bowel
• Feeling sick or being sick
Effects on the nervous system
• Loss of knee jerk reflex
• Coma
Other effects
• Slurred speech or double vision.
• Flushing
• Drowsiness
• Confusion
• Muscle weakness
• Feeling thirsty.
If any of the side effects gets serious, or if you
notice any side effects not listed in this leaflet,
please tell your doctor or nurse.

5. How to store Magnesium Sulphate
Keep out of the reach and sight of children.
Do not use it after the expiry date on the label.
The expiry date refers to the last day of that
Store below 25ºC.
Your doctor or nurse will make sure your
medicine is correctly stored and disposed of.

The other ingredients are sodium hydroxide,
sulphuric acid and water for injection.
What Magnesium Sulphate Injection looks like
Magnesium Sulphate 50% w/v Solution for
Injection is a sterile solution.
It contains 1 g of magnesium sulphate in
each 2 millilitres (ml).
It comes in packs of 1, 5, or 10 ampoules,
each containing either 1 ml, 4 ml or 40 ml
of solution.
Not all pack sizes may be marketed.
Marketing Authorisation Holder
UCB Pharma Ltd, 208 Bath Road, Slough,
Berkshire SL1 3WE, UK.
Recipharm Ltd, Vale of Bardsley,
Ashton-under-Lyne OL7 9RR, UK
This leaflet was last updated November 2009

If this leaflet is difficult to see
or read or you would like it in
a different format, please
contact: UCB Pharma Ltd, 208
Bath Road, Slough, Berkshire,
SL1 3WE, UK.

6. Further information
What Magnesium Sulphate Injection contains
In active ingredient is Magnesium Sulphate
BP 50% w/v.


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Source: Medicines and Healthcare Products Regulatory Agency

Disclaimer: Every effort has been made to ensure that the information provided here is accurate, up-to-date and complete, but no guarantee is made to that effect. Drug information contained herein may be time sensitive. This information has been compiled for use by healthcare practitioners and consumers in the United States. The absence of a warning for a given drug or combination thereof in no way should be construed to indicate that the drug or combination is safe, effective or appropriate for any given patient. If you have questions about the substances you are taking, check with your doctor, nurse or pharmacist.