Seven-day postnatal rats were rendered hyperglycemic by the SC injection of 50% glucose, following which they were exposed to hypoxia with 8% oxygen. The glucose-treated animals survived more than twice as long as saline-treated littermates. Other hyperglycemic and control rat pups were subjected to hypoxia-ischemia by unilateral common carotid artery occlusion combined with 2 hours of hypoxia. Neuropathologic analysis of recovered animals at 30 days of age showed that the brains of the glucose-treated animals were no more damaged than those of the saline controls (p > 0.05). The finding indicates that, unlike adults, glucose supplementation and its associated hyperglycemia in the immature rat does not increase the extent of hypoxic-ischemic brain damage.