We treated with PEI 81 patients carriers of autonomous thyroid nodule, 65 toxic and 16 non toxic, all with undetectable serum TSH and suppressed extranodular tissue on scintigraphy. The treatment schedule was: 1-2 sessions per week, 1-8 ml per session, 3-13 sessions in total, In relation to the size and the therapeutic response. The signs of hyperthyroidism disappeared in all cases. Complete cure was obtained in 51 patients; hormonal remission was obtained in 24 patients; partial compensation was obtained in six patients. No recurrences were observed, but two dysphonias lasting three months were reported. PEI seems to be an alternative to surgery and 131I for the ablation of toxic nodules with a volume less than 30 ml.