IgG and IgM concentrations in tears of multiple sclerosis patients (n = 38) are increased compared to normal controls (n = 23). The occurrence of oligoclonal tear IgG bands (7.9%)--as determined by immunoblotting--did not differ between groups. Our findings suggest an altered reactivity of the secretory immune system in MS patients, but did not differ from findings in patients with eye affections or wearing hard contact lenses.