Carbimazole is a drug that is used to treat an overactive thyroid. Such hyperfunction can have different triggers and manifest itself through different symptoms.

Symptoms of an overactive thyroid include:

  • Weight loss,
  • Feeling unwell in warmth
  • sleep disorders
  • general restlessness
  • Tremble
  • moist, warm skin and
  • a faster beating heart

Carbimazole belongs to the group of "thyreostatics", which roughly translates as "inhibitor of the thyroid gland".

The use of anti-thyroid drugs - including carbimazole - can have different goals: in Graves' disease, a relatively common disease of the immune system that causes an overactive thyroid, anti-thyroid drugs are used until the disease resolves on its own. Before various operations, an overactive thyroid must be treated with anti-thyroid drugs to make problems during the operation less likely.

Anti-thyroid drugs are very often used to reduce the severity of the symptoms of an overactive thyroid until it is finally treated by surgery (e.g. removal of the thyroid or treatment with radioactive iodine). Only rarely, e.g. If patients cannot be operated on because of other diseases, thyreostatics are used as a permanent form of treatment for overactive thyroid.

Read more on this topic: Therapy of hyperthyroidism


Carbimazole is taken as a tablet and works on the thyroid gland. It inhibits there the Production of the thyroid hormones thyroxine and triiodothyronine. For this purpose, it is first in his gastrointestinal tract after being absorbed effective form thiamazole transformed.

The thyroid gland needs to manufacture the hormones Iodinewhich is built into the hormone levels via certain enzymes. The Thyroid hormones influence many body functions, for example the Heat and energy balance as well as the metabolism. Normally, the thyroid gland is precisely regulated in its function by the body. In some thyroid diseases, these regulatory mechanisms are disturbed and there is an overproduction of thyroid hormones and thus a Hyperfunction. This can be through a Variety of symptoms how Tremble, inner unrest, Racing heart and Heat sensitivity express.

Carbimazole (or thiamazole) now directly inhibits the enzymes of the thyroid glandthat allow iodine to be incorporated into thyroid hormones. As a result, less effective hormones can be produced and hyperfunction is combated. If the dosage is sufficient, the associated symptoms will also disappear after a few days. When carbimazole too high a dose too strong an inhibition of the thyroid function can lead to a Subfunction come. In contrast to hyperfunction, typical symptoms are fatigue, freezing and weight gain.

The effectiveness will also like it influencedhow much iodine is in the body. At Excess iodine it works worse, at Iodine deficiency on the other hand better.

Carbimazole and alcohol

Carbimazole is one of the drugs for which it is to no direct interaction with alcohol comes. Caution is advised, however, due to the fact that carbimazole is often prescribed for the thyroid disease Graves disease. If you suffer from this disease, you often tolerate alcohol very poorly and this can have a negative impact on the disease. Carbimazole and alcohol are generally compatible, due to the condition underlying treatment it should avoided become, alcohol to consume in larger quantities.

Side effects

Carbimazole can be different Side effects trigger.
At Overdose of carbimazole can lead to a Subfunction of the thyroid come with the following symptoms:

  • Weight gain
  • stronger fatigue and Listlessness
  • constipation
  • dry skin
  • depressions and
  • Slowing of the heart

Furthermore, a allergic reaction occur on the drug, among other things Skin changes, fever, dizziness, a headache, diarrhea and swollen joints can come. The most serious and at the same time very rare side effect is the so-called "Agranulocytosis“Where the number at certain Defense cells in the blood is decreased. Agranulocytosis leads to fever, death of various areas of the skin and mucous membranes, and susceptibility to infectious diseases.

Side effect on the eyes

Side effects on the eyes are on therapy with carbimazole not to be expected. If you ask Changes in the eyes like blurred vision or a protruding eye tightness, this has another cause and it should be one Visited an ophthalmologist become. Patients who, because of a Graves disease (an autoimmune disease of the thyroid) are treated with carbimazole, can develop such discomfort in the eyes. Here is the root cause but the disease itself. It is not a side effect of carbimazole, even if there is a temporal relationship to ingestion. The drug should therefore also not just canceled become.

Side effects on the skin

If carbimazole therapy has side effects, it is most often on the skin. It happens in about one in ten patients treated temporarily to a mostly mild rash, itching, Redness and Wheal formation (small punctual accumulations of water in the skin like after contact with nettles). It is about a allergic reaction of the body. Should such complaints arise timely should be a Consultation with the attending physician and this can be visited if necessary. He will be able to advise on how to proceed and a possible change in therapy. Alternatively, you can visit your family doctor.

Hair loss side effect

Hair loss is not a side effect of carbimazole or other drugs from the group of anti-thyroid drugs (including thiamazole). If hair loss occurs at the same time as the start of carbimazole treatment, a other cause exist. Most often it is a genetic or hormonal disorder. If you want to investigate the complaints, you should if necessary, consult a dermatologist. Carbimazole should continue to be taken.

Side effects of the psyche

Carbimazole works on the thyroid gland. On the Brain and on the psyche take it no influence. Mental changes or illnesses are therefore not due to carbimazole but can have another cause. If you notice changes such as listlessness or a loss of joy in life, you should get help. The first point of contact can be the family doctor. Carbimazole and any other prescribed medication should not be discontinued without consulting a doctor.


The appropriate dosage Carbimazole can vary from person to person very different be. The doctor has to consider various factors and based on them one individually tailored dosage establish.

When overactive is often first a higher dosage elected, to achieve normal function. In order to maintain this and to prevent a relapse, a lower maintenance dose changed. By checking the thyroid function by measuring the thyroid hormones in the blood, the doctor can determine whether the dosage is correct or whether it has been set too high or too low. If necessary, this is then corrected until an optimal setting has been found.

5 mg tablets

Tablets with 5 mg carbimazole as an active ingredient are more likely lower dose. They are mainly prescribed when normal thyroid function through more concentrated carbimazole already achieved and you want to keep it. The appropriate amount of active ingredient that a patient needs for normal thyroid function, however, varies widely and depends on many factors.

10 mg tablets

Carbimazole with an active ingredient content of 10 mg is proportionate high dose and will especially when starting treatment for hyperfunction used. If normal function is restored as a result, a lower dose is usually used for maintenance purposes. However, if the hyperfunction persists below 10 mg or if normal thyroid function cannot be achieved, the dosage is maintained for longer or, if necessary, even increased.


Carbimazole is used to reduce the function of the thyroid gland. Therefore, the indications are based on all diseasesthat become a Hyperthyroidism to lead.

One of them is the Graves disease. With this so-called Autoimmune disease the body produces certain proteins (antibodies) that attach to the thyroid gland and give the signal to produce as many thyroid hormones as possible. In Graves disease, the Treatment with carbimazole usually one Healing soughtwhich is achieved in about 50% of the cases. If it is unsuccessful, another therapy such as surgery is usually recommended.

Another disease that leads to hyperfunction and for which there may be an indication for carbimazole is Thyroid autonomy. Thyroid tissue has become detached from the body's control mechanisms and produces thyroid hormones unchecked. When thyroid autonomy is no cure achieved through carbimazole treatment. The therapy can, however to bridge until, for example, an operation is performed.

Further indications for Cabimazol are the Preparing the thyroid for an operation as well as the Prevention of hyperfunction, if iodinated contrast agent to be given for a radiological examination.

Carbimazole in pregnancy

Also in the pregnancy is a Treatment with carbimazole is generally possible and sometimes even to be recommended. If the mother has an overactive thyroid, this can also have dangerous consequences for the unborn child and even lead to miscarriage.

In autoimmune disease Graves disease can those responsible for the disease antibody even pass into the child's blood and lead to hyperfunction there as well. On the other hand, carbimazole also has an influence on the child and can lead to hypofunction. That's why she should Dosage during pregnancy as low as possible be chosen and The benefit and risk of therapy are weighed. Usually, treatment of overactive during pregnancy is then recommended. In most cases, it is not carbimazole but propylthiouracil, which belongs to the same drug group, that is prescribed for pregnant women.


Carbimazole should not taken be when a Hypersensitivity to one of the ingredients of the tablets is known.

Should also be a abnormal change in the blood count with a lack of immune cells (granulocytopenia) the drug not used become.

A Gallbladder disease, in which the outflow of bile is disturbed, as in some people with gallstones, also speaks against treatment with carbimazole. Carbimazole is excreted in the bile and if the outflow of bile is disturbed, it may remain in the body for too long.

A greatly enlarged thyroid (Goiter or goiter), which narrows the windpipe, may speak against taking the drug.

No clear counter-indication on the other hand is one pregnancy or if a patient is currently breastfeeds. In individual cases the Doctor weigh upwhether carbimazole is prescribed. If necessary, this happens despite possible counter-indications if the advantages of a therapy outweigh this.

Active ingredient and interactions

Carbimazole is both the name of the active ingredient and the trade name of the drug. over possible interactions with other drugs should the attending physician to inform. As with all drugs, these can also occur with carbimazole. Basically, it is important to always tell the doctor all medication that is being taken. This also includes over-the-counter and herbal supplements such as Johannis herbs or Vitamin supplements. It should also be noted that the Effect of carbimazole as a function of dietary iodine intake increased (iodine deficiency) or decreased (iodine excess).


If there is an indication for treatment with carbimazole and the doctor recipe is exhibiting, the Health insurance usually covers costs. This applies to both statutory and private insurance. If you buy the prescription drug in an online pharmacy, the prices for 100 tablets are between 15 and 20 euros. Carbimazole should never be taken without a doctor's prescription.

Alternatives to carbimazole

Alternatives to carbimazole are fundamental similar drugs from the group of anti-thyroid drugs how Thiamazole or Perchlorate. Those who cannot tolerate thyroid drugs, show counter-signs or do not want or are not allowed to take the drug for other reasons have various alternatives.

On the one hand, a so-called Radioiodine therapy be performed. The Destruction of the diseased thyroid or parts of it through a targeted irradiation from the inside. On the other hand, one leads surgical removal of the thyroid gland to a cure of the disease and thus represents a possible alternative to treatment with carbimazole. However, in the sequence lifelong thyroid hormones taken as tablets become.

Maybe one will also come Treatment with beta blockers in question. They alleviate some overactive symptoms such as restlessness and a racing heart. However, it is a so-called symptomatic therapy, that is, the symptoms are treated, but not the cause.