Objective: This report describes 12 patients with long standing MS developed demyelinating neuropathy ( PN ) and response to methyl prednisolone ( MP) and intravenous immunoglobulin ( IG ). Background MS is primarily a central nervous system disorder. The peripheral nerve demyelination is seldom noted. Association of PN in MS can increases the overall disability and worsens the ambulation. It is important to identify these patients and subject to prompt treatment to remedy the PN. Design/Methods: 12 patients ( 8 W; 4 M ) with MS developed progressive weakness and subsequently on EMG / NCV studies, noted to have sufferred from demyelinating neuropathy. Prior to this presentation each ambulated with cane or walker. As the weakness and numbness progressed the tendon reflexes were diminished with decreased peripheral sensation. Each received 1000 mg / intravenous ( IV ) MP for 6 days and IV IG ( 0.4 gm / kg body weight ) for 5 days. After these each patient received tappering doses of ora prednisone and maintenance IG IV infusions once a month for 6 - 8 months. Results: The EMG parameters were suggestive of demyelinating PN. Each patient responded well to treatmrnt and in about 5 months, the patients responded well to treatment. In about 5 months, all returned to premorbid state. The spinal fluid studies revealed increased protein with normal cell count. Conclusions: PN may appear in longstanding MS and mostly were demyelinating in type. Aggressive treatment with MP and IG were helpful. It is important to rule out other causes of PN, for eample, diabetes, B-12 deficiency, vasculitis etc. Disclosure: Dr. Baruah has nothing to disclose. Dr. Baruah has nothing to disclose.