['To describe the use of allogeneic serum eye drops to treat 2 patients with chronic graft-versus-host disease (GVHD)-induced severe ocular surface disease.', 'Small case series.', "Conventional therapy failed to control the ocular symptoms of 2 patients with GVHD who presented with severe dry eye syndrome. Because autologous serum was unavailable in these cases, we used allogeneic serum eye drops as an alternate option for treating their ocular surface disease. Both donors had serologic tests performed before donation. Use of the allogeneic serum eye drops had a beneficial clinical effect, with marked attenuation of the patients' symptoms. This therapy proved to be safe during 10 months of treatment."] Does allogeneic serum eye drop for the treatment of severe dry eye in patients with chronic graft-versus-host disease?