Infections of burn wounds are the source of significant problems in burn patients. Early excision of eschar tissue is an ideal solution to avoid sepsis. When early excision is not feasible, the application of topical antimicrobial formulations may be used to control burn wound sepsis. An understanding of the barrier properties of eschar tissue is essential for optimal design of topical antimicrobial formulations. To date, little research has been conducted on the permeability of eschar. Silver sulphadiazine (SSD) is the most frequently used topical agent in burn management. In this study, the permeation of sulphadiazine from aqueous saturated solutions of SSD through human full-thickness burn eschar tissue was studied and compared with permeability through silicone and Carbosil as model membranes. The permeation of sulphadiazine through eschar tissue was significantly higher than that through silicone and Carbosil membranes (P < 0·05). Deconvolution of the data showed that the apparent sulphadiazine diffusion coefficient was much higher in eschar tissue and was comparable to transport through an aqueous protein gel. Further studies on a greater number of compounds are suggested to elucidate the utility of such membranes as predictive models of drug permeability through eschar tissue.