Lack of levamisole effect on experimental herpes keratitis.

Levamisole, which is an anthelminthic, can restore depressed cell-mediated immunity (CMI) under some circumstances. In a controlled trial of experimental herpetic keratis in rabbits, levamisole was found to have no significant effect on acute herpetic keratitis or its recurrence rate. This is consistent with previous findings that other nonspecific CMI stimulation had no effect on recurrences of experimental herpes keratitis. Because of the known tendency of levamisole to produce agranulocytosis, we believe it should not be used in man unless proven effective in a carefully controlled double-blind study.