Explanation

Chlorphenamine maleate (also called ALLERcalm® or Piriton®) is a medicine for treating allergies such as hay fever, itchy skin rashes, food allergy and allergic reactions to insect bites.

How does chlorphenamine maleate work?

Chlorphenamine maleate is a type of medicine called an anti-histamine. It works by blocking histamine - the chemical that causes the symptoms of allergies in your body.

What does it look like?

Chlorphenamine maleate comes as a yellow tablet that you swallow with water or as a clear syrup.

It is also available as an injection for treating bad allergic reactions or anaphylaxis. You will usually only get this in a hospital though.

How much do I have to take and when?

You can take one tablet or one measured spoonful of chlorphenamine maleate syrup every four to six hours. You shouldn't take it more than six times in one day (24 hours). If you are taking the syrup your doctor should tell you how much to measure out each time.

If you are having injections of chlorphenamine maleate, your doctor or a nurse will make sure that you have the right dose. How much you have and how often will depend on how bad your allergic reaction is, your age and how much you weigh.

But what if I don't feel like taking it?

Taking chlorphenamine maleate will help control the symptoms of your allergic reaction. If you don't take it, the allergic reaction may get worse and could be very dangerous.

What should I do if I forget to take it?

If you forget to take your chlorphenamine maleate, don't worry. Just take your next dose as normal at the usual time. Don't take twice as much next time to catch up. Remember the three Ds: Don't Double Dose!

If you are having injections, your doctor or nurse will make sure you have your dose at the right time. If you think you have missed an injection, tell an adult looking after you about it.

What if I take too much?

If you take too much, tell your doctor or an adult or go to the hospital straight away. If you go to the hospital take your medicine with you so they can see what you have taken.

The things you might notice if you take too much are:

feeling very sleepy

seizures

trouble breathing or stopping breathing at times

twitching or shaking that you can't stop

What are the side effects I am most likely to get?

Like any medicine, chlorphenamine maleate can cause side effects. The most common side effect is feeling sleepy. Other side effects are:

having trouble concentrating

blurry vision

upset stomach

nausea (feeling sick)

diarrhoea (runny poo)

If you notice these or any other side effects, tell your doctor or an adult who looks after you about it.

What other side effects might I get?

Chlorphenamine maleate can cause you to have an allergic reaction, but it is unlikely. It could be very serious though so if you notice swelling, redness or itching anywhere or you are having trouble breathing tell your doctor straight away.

Other side effects can include:

a dry mouth

headaches

not weeing as often as usual

feeling dizzy or like you are going to faint

feeling your heart beat

losing your appetite (not feeling hungry)

yellowing of your skin or eyes

getting a skin rash or bumps on your skin

twitching muscles that you can't control

hearing a ringing in your ears

becoming overly excited

If you notice these or any other side effects, tell your doctor or an adult who looks after you about it.

Are there any other side effects you haven't mentioned?

If you are having a chlorphenamine maleate injection you may feel pain or burning where it was injected.

It is unlikely but chlorphenamine maleate can also affect the way you feel or think. If you are feeling very sad, lonely or you are not enjoying things you used to make sure you tell your doctor straight away. You might also start to feel annoyed easily or start having nightmares more often. It's important to tell your doctor about these as well.

Is it safe for me to take chlorphenamine maleate?

Before you use chlorphenamine maleate, tell your doctor about any other medical problems that you know you have, or have had in the past. This is especially important if you have:

epilepsy

glaucoma

high blood pressure

heart problems

a bad cough caused by inflamed lungs (bronchitis)

other lung problems such as asthma

liver problems

problems with your thyroid gland

diabetes mellitus

If you have ever had an allergic reaction to chlorphenamine maleate or any other anti-histamine, don't use it. Tell your doctor so that he or she can choose another medicine to treat you with.

Is it OK for me to take chlorphenamine maleate if I am already taking other medicine?

You should tell your doctor about any other medicines that you are taking, or have taken, recently, including any herbal medicines. This is especially important if you are taking, or have recently taken:

any other to help you sleep or to treat anxiety

a medicine called phenytoin that is used to treat epilepsy

medicines used to treat depression called monoamine oxidase inhibitors (MAOIs).

Is there anything else I need to know about chlorphenamine maleate?

Chlorphenamine maleate contains sugar so if you are taking it for a while you are more likely to get cavities. Make sure that you look after your teeth and brush them every morning and every night.

What if I have any questions?

If you have any other questions, you can ask your doctor, or chat to other people about chlorphenamine maleate in the Medikidz forums and virtual world, Mediland.