Profound immunosuppression occurs after major burn injuries. The ability of vitamin E to prevent post-burn immunosuppression was tested in mice using ear swelling in response to a challenge with 2,4-dinitrofluorobenzene (DNFB) as an in vivo measure of cell-mediated immunity (CMI). Vitamin E was administered to burned mice every other day for 14 days by either the topical or intraperitoneal route. Dimethyl sulphoxide (DMSO) was compared to white petroleum jelly (VAS) as a vehicle for topically administered vitamin E. Mean CMI +/- the standard error of the mean (SEM) was depressed to 55 +/- 4 per cent of normal control in untreated burned mice. Treatment with either parenteral vitamin E in corn oil or topical vitamin E in DMSO improved CMI dramatically compared to burned controls (P less than 0.005) while vitamin E in VAS had a less beneficial effect on CMI (P less than 0.05). We conclude that vitamin E is an effective immunomodulator in burned mice.