than is associated with long-term administration of antithyroid drugs and the attendant constant medical supervision. Often children are unable to maintain the careful dosage schedule needed for control of the disease. If surgery is elected, the patient should be prepared with an antithyroid drug such as methimazole in a dosage and duration sufficient to produce a euthyroid state, and then should be given iodide for seven days before surgery. Lugol’s solution, or a saturated solution of potassium iodide, 1 or 2 drops twice daily, is sufficient to induce involution of the gland.
Anti-thyroid drug therapy– Antithyroid drug therapy is the usual preferable initial therapy in children. Favorable indications for its use are mild thyrotoxicosis, a small goiter, recent onset of disease, and especially the presence of some obvious emotional problem that seems to be related to precipitation of the disease. Antithyroid drug administration necessitates much supervision by the physician and the parents, the permanent remission rate will be 50% or less , and there is always the possibility of a reaction to the medication.
There is no consensus on secondary treatment if antithyroid drugs fail.. Some physicians favor surgery if the patient and parents seem incapable of following a regimen requiring frequent administration of medicine for a prolonged period or drug reactions occur. A factor that must be remembered in selecting the appropriate course of therapy is the experience of the available surgeon. Lack of experience contributes to a high rate of recurrence, permanent hypothyroidism, or permanent hypoparathyroidism. Other physicians believe the possible but unproven risks of 131-I are more than outweighed by the known risks of operation, and 131-I treatment is increasingly accepted for patients over age 15. If antithyroid drugs are chosen as primary therapy, the patient is initially given a course of treatment for one or two years, according to the dosage schedule shown in Table 11-9. The dosage of PTU (if used) needed is usually 120 – 175 mg/m2 body surface area daily divided into three equal doses every eight hours. Methimazole can be used in place of PTU; approximately one-tenth as much, in milligrams, is required.
Methimazole is now the preferred drug. During therapy the dosage can usually be gradually reduced. Many patients will be satisfactorily controlled by once-a-day treatment. Although the plasma half-life of methimazole in children is only 3-6 hours, the drug is concentrated in the thyroid and maintains higher levels there for up to 24 hours after a dose [215.1]. The program is similar to that employed in adult thyrotoxicosis. It is sensible to see the child once each month, and at that time to make sure that the program is being followed and progress made. Any evidence of depression of the bone marrow should prompt a change to an alternative drug or a different form of treatment, as discussed below. At the end of one or two years the medication is withdrawn. If thyrotoxicosis recurs, a second course of treatment lasting for one year or more may be given. A decrease in the size of the goiter during therapy is good evidence that a remission has been achieved. Progressive enlargement of the gland during therapy implies that hypothyroidism has been produced. This enlargement can be controlled by reduction in the dose of antithyroid drug or by administration of replacement thyroid hormone. There is no adequate rule for deciding when medical therapy has failed. After courses of antithyroid drug therapy totaling two to four years and attainment of age 15, if the patient still has not entered a permanent remission it is probably best to proceed with surgical or 131-I treatment. Barrio et al (215.1) reported on truly long term antithyroid drug therapy, which achieved 40% remissions in pediatric patients, with average time to remission of 5.4 years. Non-remitters were cured by RAI or surgery. Leger reported a similar program with 50% of children appearing to enter a permanent remission (215.12). Occasionally a drug reaction develo