Drug delivery to the nervous system.

Delivery of drugs to the nervous system remains a challenge despite advances in our understanding of the mechanisms involved in the development of neurodegenerative disorders and the actions of neuroactive agents. Drug accessibility to the central nervous system is limited by the blood-brain barrier; although the peripheral nervous system is more accessible than the central nervous system, problems are still encountered, mainly owing to the poor stability and considerable side effects of many neuroactive compounds when administered systemically. Microencapsulation of neuroactive compounds and living cells producing such substances can overcome some of these shortcomings for delivery to the nervous system.