The purpose of this study was to compare the clinical outcomes of intravenous immunoglobulin (IVIg) therapy to conventional immunosuppressive therapy in patients with mucous membrane pemphigoid (MMP), also known as cicatricial pemphigoid (CP), whose disease progressed to involve the eye. Before ocular involvement, all the patients in this study were diagnosed and treated with immunosuppressive agents, for biopsy-proven MMP, affecting the skin and/or mucous membranes, other than the conjunctiva. Eight patients in group A were treated with IVIg after the diagnosis of ocular cicatricial pemphigoid (OCP) was established. The efficacy and safety of IVIg therapy were compared to a clinically similar group of eight patients treated with conventional immunosuppressive therapy (group B). The inclusion criteria for both groups were: (1). presence of MMP at extraocular sites confirmed by biopsy before entry into the study; (2). entry into the study occurred when ocular involvement was noted and confirmed by biopsy; (3). presence of conventional immunosuppressive therapy at the time of ocular involvement; (4). a minimum of 18 months of follow-up after diagnosis of ocular involvement. The mean length of the therapy, after the onset of ocular involvement, was 24 months (range 16-30) in group A and 45 months (range 21-90) in group B. The median time between initiation of therapy and clinical remission in group A and group B was 4 and 8.5 months, respectively. This difference was statistically significant (P < 0.01). No recurrence of ocular inflammation was recorded in any of the patients in group A. On the contrary, at least one recurrence (median 1) was recorded in five patients in group B (range 0-4). This difference was statistically significant (P < 0.05). All eight patients in group A and group B presented to the ophthalmologist in stage 2 of OCP at the time of the initial visit. At the last follow-up visit, no progression to advanced stages of OCP was recorded in all eight patients in group A. On the contrary, only four patients in group B remained in stage 2 of OCP at the last follow-up exam. The conjunctival scaring progressed from stage 2 to stage 3 in the remaining four patients of group B. At the last follow-up visit, both eyes of each patient in group A were free of inflammation. Some level of conjunctival inflammation at the last follow-up visit was noted in five patients in group B (range 0-1.5, P < 0.05). Both groups of patients were studied during the same time period. The results of this study suggest that ocular involvement in patients with MMP may be considered an indication for initiating IVIg therapy, since it was more effective in arresting progression of OCP, when compared to conventional immunosuppressive therapy. These data indicate that IVIg produced a faster control of the acute inflammation and that no recurrences were observed during the follow-up. This clinical difference could be because of the reduced production of pathogenic antibody, and/or restoration of the immunoregulation, which may have been disturbed.