How does carbimazole work?
Carbimazole blocks the thyroid gland from producing too much thyroxine (T4) and triiodothyronine (T3), hormones that control metabolism and energy levels.
What is carbimazole used to treat?
Carbimazole is commonly prescribed for:
- Hyperthyroidism (overactive thyroid)
- Graves’ disease (an autoimmune condition causing hyperthyroidism)
- Preparing the thyroid for surgery or radioactive iodine therapy
Who can take carbimazole?
Carbimazole is suitable for most adults and children, as prescribed by a doctor.
Who might not be able to take carbimazole?
Carbimazole may not be suitable if you:
- Have severe liver disease
- Have a history of bone marrow problems or blood disorders
- Are allergic to carbimazole or similar medications
- Are pregnant or planning to conceive (discuss with your doctor)
Can I take carbimazole if I’m pregnant or breastfeeding?
Carbimazole may be used during pregnancy, but at the lowest effective dose. It is usually avoided in the first trimester. If breastfeeding, your doctor may recommend an alternative treatment.
What if I miss a dose?
If you forget a dose, take it as soon as you remember. If it’s close to your next dose, skip the missed one—do not take two doses at once.
How effective is carbimazole?
Carbimazole is highly effective at controlling thyroid hormone levels when taken as prescribed. It may take weeks to months to see full benefits.
What should I do if I take too much?
Taking too much carbimazole can cause symptoms of hypothyroidism (underactive thyroid), including fatigue, weight gain, and cold intolerance. If you think you’ve taken too much, seek medical advice.
What dose of carbimazole is usually taken?
- Starting dose: 20mg to 60mg daily, divided into smaller doses
- Maintenance dose: 5mg to 15mg daily
Your doctor will determine the correct dose based on your thyroid function tests.
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What are the side effects of carbimazole?
Common side effects include:
- Nausea or stomach discomfort
- Headache
- Mild skin rash or itching
- Joint pain
Serious side effects, such as fever, sore throat, mouth ulcers, or signs of infection (which could indicate a blood disorder), require urgent medical attention.
How should I take carbimazole?
Carbimazole is taken as tablets, usually once or multiple times daily, with or without food.
When should carbimazole be taken?
Carbimazole should be taken at the same time each day, as prescribed by your doctor.
What are the brand names for carbimazole?
Carbimazole is available as a generic medicine, but some branded versions include:
- NeoMercazole
Final thoughts
Carbimazole is an effective treatment for hyperthyroidism, but it should be taken exactly as prescribed. Regular blood tests may be needed to monitor thyroid function. If side effects occur, speak to your doctor or pharmacist.
