Antithyroid medications

III.b.1.6. Radioactive iodine. Radioactive iodine (Iodine-131) is a radioactive isotope of iodine, usually taken in an oral solution formulation as sodium 1. Given orally as sodium I, radioactive iodine is rapidly absorbed, concentrated and stored in the thyroid follicles. The therapeutic effect depends on beta-ray emission and destruction of thyroid parenchyma manifests some weeks after treatment. It is relatively safe, cheap, painless and avoids side effects associated with surgery. It is widely regarded as the treatment of choice in adults with toxic multinodular goiter, toxic nodule and people who relapse after a course of antithyroid medication. 

Antithyroid medications methimazole, methylthiouracil Antihypertensives beta blockers, captopril, enalapril Levo-dopa... 

Hyperthyroidism is treated by administering antithyroid medication, which inhibits thyroxine and triiodothyronine production. These are ... 

Three common treatment modalities are used in the management of hyperthyroidism surgery, antithyroid medications, and radioactive iodine (RAI) (Table 73-5). The overall therapeutic objectives are to eliminate the excess thyroid hormone and minimize the symptoms and long-term consequences of hyperthyroidism. Therapy must be individuahzed based on the type and severity of hyperthyroidism, patient age and gender, existence of nonthyroidal con-... 

Which antithyroid medication inhibits both iodine organification, and the conversion of T, (thyroxine) to T3 (triiodothyronine) ... 

Nine of the patients were shown to be hyperthyroid clinically, biochemically, and by radioiodine uptake, but not by biological half-life three patients were found to be hypothyroid by the same criteria. As with the euthyroid patients, none had received thyroid or antithyroid medication or extraneous iodine. 

However, our study, carried out in Delhi after salt iodization, seems to suggest that iodine intake may lead to an alteration in the response of Graves disease to treatment with antithyroid medication. In 1988, 50% of the patients with Graves disease in Delhi became euthyroid after 3 weeks of carbimazole treatment (Jones et al., 1988). This smdy was carried out one year before the ban on the sale of edible noniodized salt in Delhi was introduced. In 1999, 10 years after there was universal salt iodization in Delhi, only 15% of patients with Graves disease studied in the same hospital were euthyroid after 3 weeks of treatment with the same dose of carbimazole (Ahluwalia et al., 2001). When treated with 30 mg/day of carbimazole, 15.4% had normalized serum T3 levels and 26.9% had normalized serum T4 levels after 3 weeks of treatment. After 6 weeks of treatment, 38.5 and 53.8% of the patients with Graves disease had normalized serum T3 and T4 levels, respectively. This seems to suggest that the response of Graves disease to carbimazole has become poorer with the increase in iodine consumption. 

Table 87.6 Response of Graves disease to antithyroid medication in relationship to urinary iodine...

A similar observation of a decrease in the remission rate in Graves disease, as iodine ingestion has increased over the years, has been reported in the United States (Wartofsky, 1973). A delayed response to treatment with antithyroid medication has also been observed in Europe (Benker... 

The response of Graves disease to treatment with antithyroid medication is delayed after iodization. The response may be poorer in patients with higher urine iodine levels. 

For children less than 5 years of age, we consider antithyroid medications as a first-line therapy. Radioactive iodine has also been successfully used in this age group without an apparent increase in cancer rates. Yet, it may be best to defer radioactive iodine therapy because of the possible increased risks of thyroid cancer after radiation exposure in very young children in the event that any thyroid tissue remains after radioactive iodine therapy, and to avoid the low level whole body irradiation associated with radioactive iodine. 

There is fittle evidence that use of antithyroid medications beyond 1 or 2 years increases the likelihood of spontaneous, long-term remission. 

Antithyroid medication use in children and adolescents is associated with minor and major side-effects. Although the use of antithyroid medications is a standard practice, the use of antithyroid medications involves definite risks. 

The client diagnosed with hyperthyroidism is prescribed the antithyroid medication propylthiouracil (PTU). Which statement by the client warrants immediate intervention by the nurse ... 

The antithyroid medication may affect the body s ability to defend itself against bacteria and viruses therefore, the nurse should intervene if the client has any type of sore throat, fever, chills, malaise, or weakness. 

KoreUtz JJ, McNally DL, Masters MN, Li SX, Xu Y, Riykees SA. Prevalence of thyrotoxicosis, antithyroid medication use, and complications among pregnant women in the United States. Thyroid 2013 23(6) 758-65. 

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