Suxamethonium Chloride 50 mg/ml Solution for Injection – patient leaflet, side effects, dosage

1. What Suxamethonium Injection is and what it is used for

Suxamethonium Injection contains the active substance suxamethonium chloride.

This belongs to a group of medicines called muscle relaxants.

Suxamethonium chloride is used:

• to relax muscles during operations on adults and children,
• to help insert a tube into the windpipe (endotracheal intubation), if a person needs help to breathe.

2. What you need to know before you use Suxamethonium Injection

You should not be given Suxamethonium Injection

• if you are allergic to Suxamethonium Chloride, any other muscle relaxants or any of the other ingredients of this medicine (listed in section 6)
• if you or your family have reacted badly to an anaesthetic before such as a very high body temperature (malignant hyperthermia)
• if your doctor has told you that you suffer from abnormal cholinesterase activity (cholinesterase is an enzyme that breaks down acetylcholine)
• if you have abnormally high levels of potassium in your blood (hyperkalaemia)
• if you have muscle weakness and wasting of muscle tissue (Duchenne

muscular dystrophy)

• if you or any of your family have a disease causing weakness of the muscles

(myotonia congenita or dystrophia myotonica)

If any of the above apply to you or if you are not sure, talk to your doctor, nurse or member of the operating theatre staff before you are given Suxamethonium Injection.

Warnings and precautions

Talk to your doctor, pharmacist or nurse before you are given Suxamethonium Injection:

• if you ever had an allergic reaction to any muscle relaxant which was givenas part of an operation
• if you are suffering from an infection that causes muscle stiffness (tetanus)
• if you are suffering from tuberculosis
• if you feel unwell
• if you have a fever
• if you have cancer
• if you suffer from a blood disease known as anaemia
• if you suffer from a lack of proper nutrition or an inability to absorb nutrients from food (malnutrition)
• if you have serious liver or kidney problems
• if you suffer from a disease caused by the body attacking itself (autoimmune disease) such as a disease of the thyroid gland (myxoedema)
• if you suffer from diseases that cause problems with the joints (collagen disease)
• if you suffer from heart problems (including heart attacks, heart disease or an irregular heart beat)
• if you are having or have had in the past treatment to your blood known as plasmapheresis therapy
• if you have had any head injuries
• if you are recovering from major trauma or severe burns
• if you have suffered a spinal cord injury, nerve injury or sudden muscle wasting
• if you have a muscle disease, for example, myasthenia gravis
• if you recently had an eye injury• if you have glaucoma (increased pressure in the eye)
• if you have not been able to walk for a long period of time
• if you have severe blood poisoning (sepsis)
• if you have recently had a blood transfusion

Children

Extra care or monitoring must be carried out on infants and children given Suxamethonium Injection..

Other medicines and Suxamethonium Injection

Tell your doctor, pharmacist or nurse if you are taking, have recently taken or might take any other medicines.

• anti-arrhythmics (medicines used to alter the rhythm of the heart) such as lidocaine, procaine and cocaine.
• antibacterials (medicines able to kill bacteria) such as neomycin, vancomycin and polymyxin B
• anticholinesterases (medicines used to treat muscle problems) such as neostigmine
• ecothiopate, a medicine used to treat raised pressure in the eye (glaucoma)
• metoclopramide, a medicine used to stop you feeling or being sick
• phenelzine, a medicine used to treat depression (monoamine oxidase inhibitor)
• promazine, a medicine used to treat restlessness and agitation
• medicines used to treat malaria such as quinine and chloroquine
• tacrine, a medicine used to treat Alzheimers disease
• ACE inhibitors
• antiepileptics (medicines used to stop fits) like carbamazepine and phenytoin
• antineoplastics (medicines used to treat cancer) such as cyclophosphamide and tretamine
• benzodiazepines (medicines which help you to relax) like diazepam and midazolam
• calcium-channel blockers (medicines which reduce the strength of the heart) such as nifedipine, verapamil or dantrolene.
• cardiac glycosides (medicines which increase heart muscle contraction) such as. digoxin
• cytotoxics (a type of medicine used to treat cancer) like. Cyclophosphamide and thiotepa
• general anaesthetics (medicines used to put you to sleep for surgery) like. propofol, fentanyl citrate-droperidol (Innovar) and ether
• magnesium salts (a dietary supplement)
• medicines that affect the nervous system (parasympathomimetics and sympathomimetics) such as. demecarium, neostigmine, donepezil, bambuterol.

Tell your doctor if you have recently been exposed to pesticides e.g. sheep dip.

Pregnancy and breast feeding

If you are pregnant or breast-feeding, think you may be pregnant or are planning to have a baby, ask your doctor for advice before you are given this medicine.

This medicine should only be used during pregnancy when your doctor decides the benefits to you are greater than any possible risk to the unborn baby.

There is insufficient information to say whether this medicine passes into breast milk. Since Suxamethonium Chloride is rapidly degraded to an inactive metabolite, no effects on the breast-feeding baby are expected.

Driving and using machines

Do not drive or operate machinery immediately after you have received this medicine because it can be dangerous. Your doctor will tell you how long you should

wait before you can drive and use machinery.

Suxamethonium Injection contains sodium

Suxamethonium Injection contains less than 1mmol sodium (23mg) per dose, i.e. essentially “sodium free”.

3. How Suxamethonium Injection will be given to you

This medicine will be given to you by a qualified anaesthetist under carefully controlled conditions, along with other medicines to help you sleep. Ventilation equipment will be used to help you breathe.

Your doctor will decide the dose and duration of treatment appropriate to your intervention.

It will depend on:

• your body weight
• the amount of muscle relaxation you require
• your expected response to the medicine.

Suxamethonium Injection will be given to you as an injection into your vein (intravenously).

If you receive more Suxamethonium Injection than you should

As this medicine will be given to you whilst you are in hospital, it is unlikely that you will be given too much, however, tell your doctor or nurse if you have any concerns.

If you have any further questions on the use of this medicine, ask your doctor, pharmacist or nurse.

4. Possible side effects

Very rarely, a sudden and severe allergic reaction to suxamethonium can occur. If you get any of the following symptoms tell your doctor or nurse immediately:

• shortness of breath, wheezing or trouble breathing
• swelling of your eyelids, face, lips, tongue or other parts of the body
• rash, itching or hives on the skin
• a collapse.

There are other serious side effects that you and your doctor must look out for.

You must tell your doctor or nurse straight away if you have any of the following:

Very common: (may affect more than 1 in 10 people)

• abdominal cramps or pain and a feeling of nausea or “fullness”
• visible twitching of muscle under the skin
• muscle pain after the operation - your doctor will monitor you for this.

Common: (may affect up to 1 in 10 people)

• raised pressure of fluid in the eye which may cause headache or blurred vision
• skin flushing
• skin rash
• high level of potassium in your blood
• speeding up or slowing down of your heart rate
• protein in the blood or urine due to muscle damage
• muscle damage which may make your muscles ache or feel tender, stiff and weak. Your urine may also look dark or be red or cola coloured.

Rare: (may affect up to 1 in 1,000 people)

• abnormal heart rhythm
• heart problems including changes in the way in which your heart beats or your heart stopping beating
• difficulty in breathing or temporary loss of breath
• difficulty in opening your mouth.

Very rare: (may affect up to 1 in 10,000 people)

• high body temperature.

Other side effects include:

Not known: frequency cannot be estimated from the available data

• excessive production of saliva
• high/low blood pressure

Reporting of side effects

If you get any side effects, talk to your doctor or pharmacist. This includes any possible side effects not listed in this leaflet. You can also report side effects directly via 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.

5. How to store Suxamethonium Injection

Keep this medicine out of the sight and reach of children.

The expiry date (EXP) is printed on the label and the carton. The first 2 digits indicate the month and the remaining digits indicate the year of expiry. Do not use this medicine after the expiry date which is stated on the carton and label. The expiry date refers to the last day of that month.

Your doctor or nurse will know how to store this medicine properly.

Keep the vial in the outer carton in order to protect from light.

The vials containing the injection solution are stored in refrigerator in their original packaging at a temperature between 2° and 8°C. Do not freeze.

This medicine should be used immediately after opening., any unused liquid should be discarded. Do not use if the vial is damaged or if the contents are discoloured or deteriorated.

The solution may be mixed with certain infusion fluids.

Chemical and physical in-use stability has been demonstrated for 24 hours at 2-8°C when diluted with these infusion fluids.

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°C to 8°C

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.

6. Contents of the pack and other information

What Suxamethonium Injection contains

The active substance is suxamethonium chloride dihydrate.

Each ml of solution for injection / infusion contains 50 mg of suxamethonium chloride dihydrate (equivalent to 36.55 mg of suxamethonium).

Each 2 ml vial contains 100 mg of suxamethonium chloride dihydrate (equivalent to 73.1 mg of suxamethonium).

The other ingredients are hydrochloric acid and sodium hydroxide (for pH adjustment), water for injections.

What Suxamethonium Chloride looks like and contents of the pack

Suxamethonium Chloride is a clear, colourless sterile solution. The solution is supplied in glass vials (small bottle). These vials are then packed into cardboard boxes. Each box contains 10 x 2ml vials.

Marketing Authorisation Holder

Medsurge Healthcare UK Ltd,

The Imex Building,

575-599 Maxted Road,

Hemel Hempstead,

Hertfordshire,

HP2 7DX, United Kingdom

Manufacturer

KM BIOSCIENCES LTD,

Hamilton House,

Mabledon Place,

London, WC1H 9BB,

United Kingdom

This leaflet was last revised in May 2026.