A methimazole resistant patient with Graves' disease (GD): A case report of mid-term management with herbal decoctions mainly composed of Anemarrhena Bunge

Graves' disease (GD) is the most common cause of hyperthyroidism. Anti-thyroid drugs, including methimazole, are the most commonly selected treatment option for this condition. But for decades, no additional drug option has been added. Anemarrhena Bunge has been used in many herbal decoctions for patients who had hyperthyroidism-like symptoms, such as sweating, heat intolerance, and anxiety. In this case study, a patient with GD who had once achieved therapeutic goals with methimazole but then re-developed hyperthyroidism was treated with only herbal decoctions, and achieved euthyroidism, normalization of T3, T4 levels for 13 months and maintenance of thyroid stimulating hormone (TSH) levels for 8 months and TSH binding inhibitory immunoglobulins (TBII)-negative status for 13 months (TSH and TBII level before treatment: 0.01 μIU/mL, 10.94 IU/L; TSH level normalization after 14 months from the initiation of the treatment: 0.75 μIU/mL, TBII level normalization after 9 months from the initiation of the treatment: 0.8 IU/L). The patient did not report any adverse effects related to this treatment. A herbal decoction with Anemarrhena Bunge might be effective in patients who are resistant to methimazole treatments, a finding which needs further investigation in future.