6
Graves' Disease
RAI
4. Because RAI treatment of GD can cause a transient exacerbation
of hyperthyroidism, β-adrenergic blockade should be considered
even in asymptomatic patients who are at increased risk for
complications due to worsening of hyperthyroidism — i.e., elderly
patients and patients with co-morbidities. (W-L)
5. In addition to β-adrenergic blockade (see Recs. 2 & 4),
pretreatment with methimazole (MMI) prior to RAI therapy for GD
should be considered in patients who are at increased risk for
complications due to worsening of hyperthyroidism. (W-M)
• MMI should be discontinued 2–3 days prior to RAI.
6. In patients who are at increased risk for complications due to
worsening of hyperthyroidism, resuming MMI 3–7 days after RAI
administration should be considered. (W-L)
7. Medical therapy of any comorbid conditions should be optimized
prior to RAI therapy. (S-L)
8. Sufficient activity of RAI should be administered in a single
application, typically a mean dose of 10–15 mCi (370–555 MBq), to
render the patient with GD hypothyroid. (S-M)
9. A pregnancy test should be obtained within 48 hours prior to
treatment in any woman with childbearing potential who is to be
treated with RAI. (S-L)
• The treating physician should obtain this test and verify a negative result prior
to administering RAI.
10. The physician administering RAI should provide written advice
concerning radiation safety precautions following treatment
(http://www.thyroid.org/wp-content/uploads/patients/brochures/
Radioactive_iodine_brochure.pdf). If the precautions cannot be
followed, alternative therapy should be selected. (S-L)
11. Follow-up within the first 1–2 months after RAI therapy for GD
should include an assessment of free T
4
, total T
3
, and TSH. (S-L)
• Biochemical monitoring should be continued at 4–6 week intervals for 6
months, or until the patient becomes hypothyroid and is stable on thyroid
hormone replacement.
12. When hyperthyroidism due to GD persists after 6 months following
RAI therapy, retreatment with RAI is suggested. In selected
patients with minimal response 3 months after therapy, additional
RAI may be considered. (W-L)
