Patient Leaflet Updated 19-Nov-2025 | Martindale Pharma, an Ethypharm Group Company
Chlorphenamine 10mg/ml Solution for Injection
Chlorphenamine 10mg/ml Solution for Injection
(Chlorphenamine Maleate)
1. What Chlorphenamine is and what it is used for
2. Before Chlorphenamine is given
3. How Chlorphenamine is given
4. Possible side effects
5. How to store Chlorphenamine
6. Further information
Chlorphenamine 10mg/ml Solution for Injection contains the active ingredient chlorphenamine maleate which is an antihistamine. These medicines inhibit the release of histamine into the body that occurs during an allergic reaction. This product relieves some of the main symptoms of a severe allergic reaction.
This injection is usually given to you by your doctor or someone else trained to give it to you.
You should tell your doctor before you are given this product if you:
Please tell your doctor or pharmacist if you are taking or have recently taken any other medicines, including medicines obtained without a prescription.
The following affect the way Chlorphenamine works:
Chlorphenamine may increase the effects of the following:
Tell your doctor before using any medicine. Chlorphenamine must not be given during pregnancy or breastfeeding unless your doctor believes it is essential.
Chlorphenamine may cause drowsiness and make you sleepy.
Do not drive or operate machinery until you know how this product affects you.
This medicinal product contains less than 1mmol sodium (23mg) per dose of up to 4ml, i.e. it is essentially “sodium-free”.
This injection is usually given to you by your doctor or someone else trained to give it to you. You will be given the injection beneath your skin, or into a muscle, or directly into a vein.
Adults: the usual dose is 10mg - 20mg (1 or 2 ampoules), up to a maximum of 40mg (4 ampoules) in 24 hours.
Children: the dose will be calculated by the doctor, according to the child’s age or body weight:
Age 1 month to 1 year dose is given 0.25mg/kg
Age 1 to 5 years dose is 2.5mg to 5mg or 0.20mg/kg
Age 6 to 12 years dose is 5mg to 10mg or 0.20mg /kg
Age 12 to 18 years dose is 10mg to 20mg or 0.20mg /kg
The doctor may dilute Chlorphenamine with sodium chloride 0.9% to make it easier to measure and inject the small amounts required for children.
When administered into a vein, the injection should be given slowly over a period of one minute to avoid a fall in blood pressure (hypotension) or central nervous system stimulation.
This product will be given to you under medical supervision. It is therefore unlikely that you will be given too much. However, if you feel unwell, you should tell your doctor immediately.
Symptoms of overdose include sedation, seizures, stopping of breathing (apnoea), convulsions, abnormal and sustained muscle contractions (dystonic reactions) and heart failure (cardiovascular collapse).
If you have any further questions on the use of this product, ask your doctor or pharmacist.
Like all medicines, Chlorphenamine can cause side effects, although not everybody gets them.
The most common side effect is sedation, which can range from slight drowsiness to deep sleep.
The following side effects have been reported:
Elderly people may become confused and children may become excitable.
If any of these side effects get serious, or if you notice any side effects not listed in this leaflet, please tell your doctor.
If you get any side effects, talk to your doctor, pharmacist or nurse. This includes any possible side effects not listed in this leaflet. You can also report side effects directly via the Yellow Card Scheme: 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.
Keep out of the sight and reach of children.
Store below 25°C and protect from light.
Do not use after the date shown as ʻEXP’ on the carton.
Use immediately after opening. For single use only. Discard any unused contents immediately after use.
Use immediately after dilution.
Medicines should not be disposed of via wastewater or household waste. Ask your pharmacist how to dispose of medicines no longer required. These measures will help to protect the environment.
The active substance is: chlorphenamine maleate.
The other ingredients are: sodium chloride (see also end of section 2), water, hydrochloric acid (for pH adjustment) and sodium hydroxide (for pH adjustment).
Chlorphenamine is supplied in glass ampoules. Each ampoule contains 10mg chlorphenamine maleate (in 1ml of clear, colourless sterile solution for injection).
Contents: 5 glass ampoules per box.
This leaflet was last revised: August 2025
D50274
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