[Lithium acetate, a useful and well tolerated thyrostatic for selected cases of hyperthyroidism].

Lithium acetate treatment of 6 patients with hyperthyroid Graves' disease and 6 patients with toxic nodular goiter is reported. Lithium acetate was administered either as monotherapy (group A) or combined with 45 mg carbimazole or methimazole (group B). A control group of 8 patients received methimazole or carbimazole only (group C). Lithium either alone or combined with thionamide drugs consistently lowered serum thyroxine and triiodothyronine with marked clinical improvement. After 7 days of treatment thyroxine was reduced by 28% (group A), 43% (group B) and 36% (group C). The respective decrease in triiodothyronine was 42%, 50% and 46%. The differences between three groups were not statistically significant. We conclude that lithium is a useful antithyroid agent for selected patients, since it is safe and effective even in severe cases, does not interfere with radioiodine uptake for diagnostic or therapeutic purposes and provides an alternative for patients allergic to thionamides.