Thyroid Monograph - FreeCE

iodide (Lugol solution) contains 8 mg of iodide per drop, and is used for the
treatment of thyroid storm for 10 to 14 days prior to thyroidectomy.
4. Beta-adrenergic receptor blockers
Beta blockers help to promptly alleviate the sympathomimetic manifestations of
hyperthyroidism (eg, palpitations, anxiety, tremors, and heat intolerance)
regardless of its underlying cause. In patients with cardiac arrhythmias like sinus
tachycardia or atrial fibrillation with a rapid ventricular response rate, beta
blockers can function to control the heart rate. Propanolol, a nonselective beta
blocker, is preferred because of its direct effect on hypermetabolism and is most
commonly used, although other beta blockers can be given. 23 Propanolol also
partially inhibits conversion of T4 to T3 in the peripheral tissues. 4
may be the only treatment required in patients with transient forms of
hyperthyroidism, however, in patients with more sustained forms of
Beta blockers
hyperthyroidism (ie, Graves’ disease, toxic nodular goiter), definitive treatment is
10, 20, 21, 24
necessary.
Propanolol dose can start at 20 to 40 mg every 8 hours and be increased
progressively up to a maximum daily dose of 240 mg until symptoms are
controlled. Longer-acting beta blockers such as metoprolol and atenolol can also
be used. In cases where a short-acting parenteral agent is needed, Esmolol can
be administered. Beta blockers should be used with caution in patients with a
history of heart disease, obstructive pulmonary disease, asthma, or Raynaud’s
phenomenon.
5. Radioactive iodine therapy
Radioactive iodine causes selective uptake and concentration in thyrocytes.
Following oral administration, it destroys thyroid tissue, thereby controlling
hyperthyroidism effectively. This is the treatment of choice for the majority of
patients with Graves’ disease and toxic nodular goiter. High dose radioactive
iodine therapy is recommended in elderly patients, those with preexisting cardiac
disease, and patients with toxic nodular goiter or toxic adenomas. 25
Its main adverse effect is the development of postablative hypothyroidism, which
is more commonly seen in patients with Graves’ disease. Lifelong monitoring of
thyroid hormone levels is necessary because patients develop this complication
at a rate of 3% annually. Another side effect is the transient worsening of
hyperthyroidism during the first month of treatment due to radiation thyroiditis.
Opthalmopathy may develop or exacerbate in 15 percent of patients with Graves’
26, 27
disease, especially in those who smoke cigarettes. Lower dose radioactive
iodine or prednisone can be used in those patients to reduce the risk of
ophthalmopathy. 28
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