E05.0
MEDICINE TREATMENT
- Carbimazole, oral, 20–40 mg daily.
- Titrate dose according to thyroid hormone levels (T₄).
- Duration of therapy: 12–18 months.
- Durations of therapy longer than 12 months must be in consultation with a specialist.
ß–blockers
- Used to counteract excessive sympathetic symptoms, e.g. palpitations.
- Dose is titrated according to the heart rate.
- Give for 2–6 weeks, together with carbimazole until T₄ levels normalise.
- ß–blocker, e.g.:
- Atenolol, oral, 50 mg daily.
- Titrate according to symptom control up to 100 mg daily.
Radioactive iodine
In the setting of Graves’ disease radioactive iodine may be administered for failed medical therapy and may be indicated for patients with coexistent heart disease. Refer patient if radioactive treatment is contemplated.
Surgery
Seldom indicated, but to consider in the following situations: large thyroid causing obstructive symptoms, failure of anti-thyroid medicine therapy, allergy to anti-thyroid therapy, 2nd trimester of pregnancy, and not responding to or allergic to anti-thyroid medication.
Monitoring
Patients with Graves’ disease who are treated with anti-thyroid drugs should be monitored every 6–8 weeks using a serum T₄. TSH may remain suppressed for months. Once in remission, patients may be monitored less frequently to determine signs and symptoms of recrudescence of thyrotoxicosis.
Because there is a risk of neutropenia or agranulocytosis with carbimazole, therapy should be temporarily stopped and a white cell count (with differential) must be done in patients presenting with an infection or sore throat.
Post-radio-active iodine TSH and free T₄ should be checked at 6 weeks, 3, 6, 9 and 12 months and annually thereafter until either hypothyroidism occurs or patient remains euthyroid for ± 3–4 years. Although uncommon, new onset hypothyroidism can occur years later.