A Cochrane review included 13 studies with a total of 1770 subjects. All of them were of low quality. None of these trials analysed mortality, health related quality of life, economic outcomes or compliance. Compared to antithyroid drugs alone the results showed that Chinese herbal medicines combined with antithyroid drugs may offer benefits in lowering relapse rates, reducing the incidence of adverse effects, relieving symptoms, improving thyroid antibody status and thyroid function. Two trials investigated Chinese herbal medicine versus radioiodine and reported improvements in anxiety, tachycardia and heat intolerance. However, thyroid function – with the exception of restored thyroid stimulating hormone (TSH) – was not significantly altered.
Comment: The quality of evidence is downgraded by inconsistency of results; heterogeneity in content of interventions.