NZ Formulary

Carbamazepine

kar-ba-maz-e-peen

What does it do?

Carbamazepine is used to treat and prevent seizures. Sometimes it is used for other conditions, such as bipolar disorder and some types of pain.

Before you start

  • Tell your doctor if you have heart, liver, bladder, prostate or bowel problems, or if you have angle-closure glaucoma.
  • Tell your doctor if you are pregnant, planning to become pregnant, or breastfeeding.

How should you take it?

Take carbamazepine regularly as directed. You can take it with or without food.
Slow release tablet: Take with a glass of water. You can halve these, but do not crush or chew them.
Tablet: Take with a glass of water.
Liquid: Shake the bottle well, then measure carefully with an oral syringe or measuring spoon.

What if you forget a dose?

Take the missed dose as soon as possible and continue as directed.

Can you take other medicines?

Carbamazepine can react with many medicines, sometimes with severe results.

Remember to tell your pharmacist or doctor you are taking carbamazepine before starting any other medicines or treatments, including over-the-counter medicines, vitamins, herbal products or recreational drugs.

What side effects might you notice?

Side EffectsRecommended action

Skin rash, skin peeling or blisters

Stop taking and see your doctor immediately

Suicidal thoughts

Reduced number of blood cells that fight infections or help your blood to clot - symptoms include: fever, chills, sore throat or generally feeling unwell, or easy or unusual bruising or bleeding

Symptoms of liver problems including: yellow skin or eyes, itching, dark urine, pale bowel motions, abdominal pain

Tell your doctor immediately

Unusual eye movements

Confusion, loss of co-ordination/walking or handwriting problems

Tell your doctor

Dry mouth, blurred vision, constipation or trouble peeing (anticholinergic effects)

Tiredness or weakness

Tell your doctor if troublesome

Dizziness, drowsiness

Nausea, vomiting

Common when you first start but should improve. Tell your doctor if troublesome.

If you notice any other effects, discuss them with your doctor or pharmacist.

Other information:

  • Grapefruit, grapefruit juice or sour/Seville oranges may react with carbamazepine. Discuss with your pharmacist.
  • Some contraceptives may not work as well while you are taking carbamazepine, and for 4 weeks after stopping. Discuss with your doctor or pharmacist.
  • Carbamazepine can impair your ability to do tasks such as driving or using machines. Alcohol makes this worse. Discuss your risk with your health professional. (search NZTA - Are you safe to drive?)
  • You may need blood tests from time to time to make sure you are taking the right dose of carbamazepine.
  • Do not stop taking carbamazepine without talking to your doctor first, unless you have a skin rash (see Side Effects).