Infusion therapy using low-molecular dextran in combination with high-dose cortisone was modified from Stennert's original protocol and indicated in 50 cases of Bell's palsy. The effects of infusion were compared with the outcome in 36 cases treated by orally-administered steroids and vasodilators. In the case of incomplete palsy, the recovery rate was excellent regardless of the mode of treatment. If the palsy is not progressive, it is not necessary for patients with this condition to have infusion therapy. In the case of complete palsy, 95% of those with normal nerve excitability (NE) experienced complete recovery when treated by infusion. However, only 71% of this group experienced complete recovery when treated with oral administration. In the group with diminished or absent NE, complete recovery was obtained in 58% of the patients treated with infusion, whereas only 18% recovered completely when given oral administration. Thus, the recovery rate increased sharply in the case of infusion therapy. Therefore, the above-mentioned method of infusion therapy is indicated in cases of complete or progressively incomplete Bell's palsy except in those cases where its use is contra-indicated for some other reason.