This large-animal intracerebral drug administration unit is designed to allow the delivery of drugs or other agents to discrete loci within the brains of animals while maintaining sterile conditions. It is an improvement over existing designs because it (1) maintains an absolute minimal dead space within the system, (2) is smaller in diameter (by approximately 80% than existing shunt catheters, minimizing tissue damage during placement, (3) is easily secured and requires minimal clearance over the cranium, and (4) maintains a sterile seal between the brain and periphery. Preliminary studies indicate that the device is well accepted by monkeys and is fully functional for periods up to a year. The device is intended for permanent implantation.