Carbimazole: Information for Patients

 
Carbimazole is a commonly used medicine used to treat hyperthyroidism.

What is Carbimazole?

Carbimazole is a commonly used medicine used to treat hyperthyroidism. It works by reducing the amount of thyroid hormones which your thyroid gland makes. Carbimazole may be used alone or together with other treatments for hyperthyroidism.

Severe but rare side effects of taking Carbimazole:

Carbimazole can very rarely be associated with a condition called agranulocyrtosis (low neutrophil count) which can have symptoms including sore throat, bruising or bleeding, mouth ulcers, fever, malaise.

If you experience these symptoms, you should stop the medicine and seek medical advice immediately. Your doctor will check your white blood cell count to make sure it is within normal range.

It can be rarely associated with liver impairment. If you develop any signs and symptoms of hepatic disorder (pain in the upper abdomen, anorexia, general pruritus) you should stop the carbimazole and seek medical attention.

Pregnancy

Carbimazole should not be used in pregnancy as it can cause congenital malformations.

Minor side effects of taking Carbimazole:

The most common side effects of taking carbimazole include:

  • Nausea

  • Headache

  • Arthralgia

  • Mild gastric distress

  • Mild skin rashes and pruritus can occur and these often respond to antihistamines without discontinuation of the medicine.

Most toxic reactions to carbimazole occur within 8 weeks of starting treatmetn, and generally affect patients on at least 20mg of carbimazole daily.

If you experience an advers reaction or concerning side effect, please see your GP.

To inform your endocrinologist, call reception on: (02) 9157 9095.