A leukotriene C4 and D4 antagonist is used to treat or inhibit brain inflammation and sepsis by acting to inhibit increased capillary permeability and white blood cell extravasation. Potential candidate compounds can be screened in a non-human mammal before or after administration of an inflammation inducing agent into the subarachnoid space by determining their ability to inhibit increased capillary permeability and white blood cell extravasation.