Chlorphenamine for allergies

Overview

Chlorphenamine is a type of antihistamine used to relieve allergies such as:

• Hay fever.

• Food allergies.

• Drug allergies.

• Allergic skin reactions.

• Itching caused by infections such as chickenpox.

It is also given to treat a type of allergic reaction called anaphylaxis, which is a medical emergency.

Chlorphenamine is available on prescription, or you can buy it without a prescription at pharmacies.

Chlorphenamine works by blocking the effects of histamine - a chemical that is released when the body is exposed to substances such as pollen, pet fur, peanuts, shellfish or insect bites.

Histamine causes allergic symptoms such as swelling, skin rashes, sneezing, watery eyes, and a runny or blocked nose. Chlorphenamine relieves allergic symptoms like these.

Common side effects of chlorphenamine include:

• Feeling dizzy or sleepy.

• Blurred vision.

• Headache.

• Dry mouth.

• Lack of concentration.

• Upset stomach.

• Difficulty peeing (urinating).

Children and people over 65 years of age may be more prone to side effects from chlorphenamine.

You will find a full list of side effects in the manufacturer's information leaflet supplied with your medicine.

The unwanted effects often improve as your body adjusts to the new medicine, but speak with your doctor or pharmacist if any continue or become troublesome.

If you experience any other symptoms which you think may be due to this medicine, speak with your doctor, dentist, or pharmacist for further advice.

To make sure that this is the right treatment for you, before you (or your child) start taking chlorphenamine it is important that you discuss the treatment with a doctor or pharmacist if:

• You are pregnant or breastfeeding.

• You have a problem with the way your liver works.

• You have glaucoma, a condition which causes increased pressure in your eyes.

• You have prostate problems, or if you have been experiencing any difficulty peeing.

• You know you have a blockage in your small intestines.

• You have epilepsy.

• You are taking any other medicines. This includes any medicines you are taking which are available to buy without a prescription, as well as herbal and complementary medicines.

• You have ever had an allergic reaction to a medicine.
  

• Read the leaflet included with your medicine before taking chlorphenamine.

• Take chlorphenamine exactly as advised by your doctor or pharmacist.

• The usual recommended doses are:

  • Adults and children over 12: 4 mg every 4-6 hours. Maximum: 24 mg daily (12 mg daily if over 65).

  • Children aged 6-11: 2 mg every 4-6 hours. Maximum: 12 mg daily.

  • Children aged 2-5: 1 mg every 4-6 hours. Maximum: 6 mg daily.

  • Children aged 1-23 months: 1 mg twice daily, ideally morning and evening.

• If using liquid medicine for children, measure doses carefully using the instructions on the bottle.

• You can take chlorphenamine before or after food.

• Stop taking chlorphenamine once your symptoms have eased.

• If you miss a dose, take the next one as normal. Do not take two doses together.
  

• Chlorphenamine can cause drowsiness. If you feel sleepy, do not drive or use machinery.

• Avoid alcohol while taking chlorphenamine, as it can make drowsiness worse.

• Tell your doctor or healthcare professional you are taking chlorphenamine before any operation, treatment, or allergy test.

• Chlorphenamine may make your skin more sensitive to sunlight. Use sunscreen (SPF 15 or higher) and avoid sunbeds.

Check with a pharmacist before taking other medicines alongside chlorphenamine, as some can increase side effects or interact with antihistamines.

• Keep all medicines out of the reach and sight of children.

• Store in a cool, dry place, away from direct heat and light.
  

How long does chlorphenamine take to work?

Chlorphenamine usually starts working within 30 minutes to 1 hour. Because it is a drowsy antihistamine, some people may feel sleepy soon after taking it.

The effects of chlorphenamine can last for several hours, and drowsiness may continue into the next day in some people.

Can you take chlorphenamine every day?

Chlorphenamine can be taken daily for short-term allergy relief if needed. However, long-term use should only be advised by a doctor or pharmacist.

Always follow the recommended dose and stop taking it once symptoms improve.

Can you drink alcohol while taking chlorphenamine?

It is best to avoid alcohol while taking chlorphenamine. Alcohol can increase drowsiness and make side effects worse.

Can chlorphenamine be taken with other antihistamines?

You should not take chlorphenamine with other antihistamines unless advised by a healthcare professional. Combining antihistamines can increase side effects such as drowsiness.

Can you take chlorphenamine during pregnancy?

Chlorphenamine usually can be taken during pregnancy. However, always let your doctor or midwife know that you are pregnant before taking it.