Lithium as an adjunct to radioactive iodine for the treatment of hyperthyroidism: a systematic review and meta-analysis.

Radioactive iodine (RAI) is commonly used in the treatment of hyperthyroidism but is not uniformly successful. Lithium increases thyroidal iodine retention without reducing iodide uptake, increasing the radiation dose to the thyroid when administered with RAI. Although these actions suggest that adjuvant lithium may increase the efficacy of RAI, its role as an adjunct to RAI remains contentious.