The text only version may be available in large print, Braille or audio CD. For further information call emc accessibility on 0800 198 5000. The product code(s) for this leaflet is: PL 20072/0240.
Carbimazole 20 mg tablets
Carbimazole 5 mg and 20 mg tablets
1. What Carbimazole is and what it is used for
2. What you need to know before you take Carbimazole
3. How to take Carbimazole
4. Possible side effects
5. How to store Carbimazole
6. What Carbimazole 5 mg and 20 mg tablets contain
The name of your medicine is Carbimazole 5 mg tablets or Carbimazole 20 mg tablets (called Carbimazole in this leaflet). This belongs to a group of medicines called 'anti-thyroid' medicines. Carbimazole is used for people with an over-active thyroid gland (called 'hyper-thyroidism')
Do not take Carbimazole tablets if any of the above apply to you. If you are not sure, talk to your doctor or pharmacist before taking Carbimazole.
Talk to your doctor or pharmacist before taking Carbimazole
If you are not sure if the above applies to you, talk to your doctor or pharmacist before taking Carbimazole.
Do not give this medicine to children under the age of two years because it may not be safe or effective.
Tell your doctor or pharmacist if you are taking or have recently taken or might take any other medicines.
This includes medicines obtained without a prescription, including herbal medicines. This is because Carbimazole can affect the way some medicines work. Also some medicines can affect the way Carbimazole works.
In particular tell your doctor or pharmacist if you are taking any of the following:
If any of the above apply to you (or you are not sure), talk to your doctor or pharmacist before taking Carbimazole.
If you are pregnant or breast-feeding, think you may be pregnant or are planning to have a baby, ask your doctor or pharmacist for advice before taking this medicine.
Carbimazole can cause harm to an unborn baby. If you could get pregnant, use reliable contraception from the time you start treatment and during treatment. However, to reduce the possibility of any effects on your baby:
Your treatment with Carbimazole may need to be continued during pregnancy if the potential benefit outweighs the potential risk to you and your unborn baby.
Do not breast-feed if you are taking Carbimazole. This is because small amounts may pass into the mother's milk.
If you have been told by your doctor that you have an intolerance to some sugars, contact your doctor before taking this medicinal product.
Always take this medicine exactly as your doctor has told you. Check with your doctor or pharmacist if you are not sure.
The doctor will decide on a starting dose, and then see how well it works.
The usual starting dose for the 5 mg tablets is between 4 and 12 tablets each day.
The usual starting dose for the 20 mg tablets is between 1 and 3 tablets each day.
The usual starting dose is three 5 mg tablets each day.
Your illness will usually start to improve within one to three weeks. However, it usually takes four to eight weeks to have full benefit from your treatment.
Another treatment for an over-active thyroid is called "radio-iodine". If you need radio-iodine treatment your doctor will tell you to stop taking Carbimazole tablets for a while.
If you take more Carbimazole than you should, talk to a doctor or go to a hospital straight away.
Take the medicine pack or this leaflet and any remaining tablets with you.
If you forget a dose, take it as soon as you remember. If it is time for your next dose, take both doses together.
If you have any further questions on the use of this medicine, ask your doctor or pharmacist.
Like all medicines, this medicine can cause side effects, although not everybody gets them. The side effects usually happen in the first eight weeks of your treatment. Do not be alarmed by this list of possible side effects. You may not get any of them.
If you have an allergic reaction, stop taking Carbimazole and see a doctor straight away. The signs may include: sudden rash, swelling or difficulty breathing.
In addition, if you experience any of these symptoms while taking Carbimazole you should also contact your doctor immediately:
These could be signs of muscle problems, jaundice or inflammation of the liver and under medical supervision your doctor may want you to stop taking the medicine and carry out some blood tests on you.
Do not stop taking Carbimazole until you have consulted your doctor.
Carbimazole can sometimes cause bone morrow depression which causes a reduction in the number of blood cells and reduces the ability to fight infection. If it is not treated as soon as it is detected the condition can become life-threatening. Your doctor should carry out tests to check for bone marrow depression before restarting your treatment.
If you get any of the following side effects, they normally go away while you keep taking your medicine.
Other side effects include:
The following side effects have also been reported:
If you get any side effects, talk to your doctor or pharmacist. This includes any possible side effects not listed in this leaflet. You can also report side effects directly via the Yellow Card Scheme Website: www.mhra.gov.uk/yellowcard or search for MHRA Yellow Card in the Google Play or Apple App Store.
By reporting side effects you can help provide more information on the safety of this medicine.
Ask your pharmacist how to dispose of medicines no longer required. These measures will help to protect the environment.
This leaflet was last revised in August 2023.