What’s the Optimal Dosage of Anti-thyroid Medication for Graves’ Disease?
At the 2011 Endocrine Society Annual Meeting, an abstract was presented called “Low-Dose Anti-Thyroid Medication in Graves’ Disease: Assessment of the Efficacy Based on a Long-Term Follow-Up (Interim Report).”
The researchers were examining the optimal dosage of anti-thyroid medications for Graves’ disease; the optimal dosage is somewhat a matter of controversy. In this study, there were 119 randomly selected patients with Graves’ disease. The rate of response to the low dose anti-thyroid medication treatment regimen was assessed.
Here’s how it was done: All 119 patients (19 males and 100 female; mean age was 54.67 ± 15.72) were given anti-thyroid medications at the initial dose of 20 mg/day of methimazole (MMI). Gradually, doses were decreased. When the patient was able to maintain euthyroid (normal TSH and FT4) for at least 12 months with the minimum maintenance dose, medication was discontinued.
After the patient discontinued anti-thyroid medications, FT4, FT3, and TSH were measured every month for the first 3 months; after that, FT4, FT3, and TSH were measured every 3 months for the next 12 months. Following that period, hormone level tests were done every 2, 5, and 10 years to confirm continuous remission.
Out of the patient population of 119, 88 (73.9%) had pure Graves’ disease; 31 (26%) had Graves’ disease with an additional nodule. After treatment, 70 patients (66.1% achieved remission. There were 28 patients (26.4%) who required surgery to help control signs and symptoms of Graves’ disease; 8 patients (7.5%) needed iodine therapy.
Normal TSH was reached in 34%, 34.6%, 44%, 47.2%, 52.8%, 58.5%, and 66% during the 3rd, 6th, 9th, 12th, 24th, 60th, and 120th months, respectively.
No significant differences were noted between females in disease remission and males in disease remission.
The researchers came to the following conclusion: For the treatment of Graves’ disease, the dose of anti-thyroid medications can be safely kept to the minimum required with almost equal efficacy to that of the high dose regimen. This provides balance between possible risks and benefits of anti-thyroid medications for Graves’ disease.