Anti-thyroid Drugs: Precautions in Pregnancy, Lactation and Asthma

The thyroid gland of our body controls the body metabolism through its iodine containing hormones. Normal thyroid gland is not palpable but the enlarged thyroid gland could be felt in front of the neck and may be associated with non-toxic or toxic goitre. Goitrous gland may have normal function or under function (hypothyroidism) or over function hyperthyroidism). The exophthalmic goitre is known as Graves's disease and in this
disease the eye balls protrude due to thyrotoxicosis.

The compounds used as anti-thyroid drugs include carbimazole and propylthiouracil. Anti-thyroid drugs inhibit the formation of thyroxine and triiodothyronine (T3) in the thyroid gland. Propylthiouracil also retard the peripheral conversion of thyroxine into triiodothyronine (T3). The same drugs are also used for the treatment of thyrotoxicosis and preparation for thyroidectomy. Anti-thyroid drugs may suppress the bone marrow so blood cell counts are advisable at regular intervals during the course of treatment. Pregnant and/or lactating patients with thyrotoxicosis need to consult the endocrinologist and to reduce the dose to minimum. Patients with tracheal obstruction or asthma also need extra care during the treatment of hyperthyroidism or thyrotoxicosis. Anti-thyroid drugs may cause nausea, gastro-intestinal upset, thyroid enlargement, agranulocytosis, granulocytopenia ( low count of neutrophils and eosinophils), leucopenia (low count of white blood cells) and thrombocytopenia low count of platelets); that is why regular blood counts are advisable. Self-treatment of hyperthyroidism or thyrotoxicosis is not advisable, as it needs investigative follow up. However, carbimazole oral drug is started with a dose of 15-45mg daily in divided doses depending on the severity of the disease and maintenance dose could be 2.5-25mg daily for 12 months. For thyroidectomy preparation, the dose may be 15-45mg daily in divided doses for 2-4 weeks depending on the severity of the disease.

To know more about thyroid gland and its functions-click here: http://ntips4u.blogspot.com/2009/07/thyroid-gland-and-its-functions.html