To study the extent of systemic immunodysregulation in multiple sclerosis (MS) we measured immunoglobulin (Ig)G, A, and M levels and studied their migrational properties after agarose isoelectric focusing in serum, cerebrospinal fluid (CSF) and tear samples from 18 MS patients, 17 patients with other neurological diseases (OND), and tears and serum samples from ten normal controls (NC). A slight elevation of total IgG, IgM and IgA levels was detected in tears from patients with MS and OND compared to NC. Of the five patients (two MS, three OND) that showed IgG oligoclonal bands (OCB) in tears, only one MS patient showed unique bands in tears not seen in the paired CSF and serum. We never found IgA, and IgM OCB in serum, CSF or tear samples. Our results suggest that polyclonal Igs are systemically elevated during chronic neurological inflammatory diseases. Oligoclonal Ig in MS, although occasionally detectable in tears, is mainly confined to the central nervous system and appears restricted to class G.