Surgical resection of brain tissue is associated with tissue damage at the resection margin. Studies of ischemic brain injury in rodents have shown that administration of L-histidine and thioperamide reduces ischemic tissue loss, in part by inhibition of apoptotic cell death. In this study we tested administration of L-histidine and thioperamide in surgical brain injury in mice. Mice were randomized to one of three groups: Sham surgery (n=18), surgical brain injury without treatment (SBI) (n=33), and surgical brain injury with combined l-histidine and thioperamide treatment (SBI+H) (n=29). Surgical brain injury was induced via right frontal craniotomy with resection of the right frontal lobe. L-histidine (1000 mg/kg) and thioperamide (5 mg/kg) were administered to the SBI+H group immediately following surgical resection. Postoperative assessment included neurobehavioral scores, Evans blue measurement of blood-brain barrier breakdown, brain water content, Nissl histology, and immunohistochemistry for IgG and cleaved caspase 3. Postoperative findings included equivalent neurobehavioral outcomes at 24 and 72 h in the SBI and SBI+H groups, similar histological outcomes between SBI and SBI+H, and similar qualitative staining for cleaved caspase 3. SBI+H had increased BBB breakdown on Evans blue analysis and a trend towards increased brain edema which was significant at 72 h. We conclude that combined treatment with l-histidine and thioperamide leads to increased BBB breakdown and brain edema in surgical brain injury.