The study will take 60 patients and divide them into two groups. Group one will receive 2 injections of IVIg once a month for three months. Group two will receive 2 injections of placebo "inactive injection of sterile water" once a month for three months. Following the three months of treatment, group one will begin taking the placebo and group two will begin taking IVIg for an additional 3 months. The drug will be considered effective if patients receiving it experience a significant improvement (>15%) in muscle strength.