Six patients affected by toxic thyroid nodules (Plummer disease) were treated by percutaneous ethanol injection (PEI). Treatment was performed injecting under ultrasound guidance 2-4 mL of 95% sterile ethyl alcohol through a spinal needle (22 gauge, 75 mm length). Treatment was performed once-twice weekly and repeated as an outpatient procedure 4-6 times. PEI induced clinical improvement and hormonal control by the end of the treatment (one month) and no complications took place. After PEI all hyperfunctioning thyroid nodules became smaller at clinical and ultrasound examination. Three months after PEI hot areas appeared cold at 99mTc and 1311 scintiscan. Serum levels of FT3, FT4, AbT, AbM, TG reached the normal range and serum TSH levels were significantly increased and responsive to TRH stimulation.