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available and all are very safe but need to be taken for the rest of one's life.

Thyroid hormone treatment is given under the care of a physician and may

take a few weeks to become effective.[23]

Surgery is sometimes used to treat overactive thyroid, thyroid nodules, and

often for thyroid cancers. The surgery is quite effective but can have a few side

effects or risks:

The nerves controlling the vocal cords can be damaged.

The parathyroid glands that produce parathyroid hormone (PTH) can be

destroyed and one can develop bleeding.

If the entire thyroid gland is removed, one develops hypothyroidism, which

entails taking hormone supplements for the rest of one's life.[24]

Carbimazole is used to treat hyperthyroidism. Carbimazole is a pro-drug as

after absorption it is converted to the active form, methimazole. Methimazole

prevents the thyroid peroxidase enzyme from coupling and iodinating the

tyrosine residues on thyroglobulin, hence reducing the production of the

thyroid hormones T3 and T4 (thyroxine).

Side Effects

Whilst rashes and pruritus are common, these can often be treated with

antihistamines without stopping the carbimazole. For those patients where

sensitivity reactions can not be controlled, propylthiouracil may be used as an

alternative.

Its most serious rare side effect is bone marrow suppression causing

neutropenia and agranulocytosis. This may occur at any stage during

treatment and without warning. Patients are advised to immediately report

symptoms of infection, especially sore throats, so that a full blood count test

may be arranged. If this confirms a low neutrophil count then the drug must

be discontinued immediately, allowing for usually a prompt recovery. However

failure to report suggestive symptoms or delays in considering the possibility

of immunosuppression and its testing, can lead to fatalities. Should be usedwith caution in pregnancy as crosses the placenta barrier.