Current advances in nose to brain drug delivery.

The systemic treatments are not able to assure adequate drug concentration in the brain tissues in many neurological disorders due to the biological barriers such as the blood-brain barrier. Therefore, drug delivery systems can directly target the brain cells in a noninvasive means and bring about adequate drug in the brain is the focus in many of central nervous system (CNS) diseases. Perhaps the intranasal route and the direct anatomical connection between the nasal cavity and the brain can be supportive in the direct entry of therapeutic agents into the brain. This review paper is an insight into various considerations involved in the nose to brain drug delivery, such as the pros and cons of intranasal delivery, the anatomical and physiological features of the nose, various pathways, mechanisms of drug transport, disease perspectives, approaches to enhance the drug absorption with brief emphasis on types, and examples of agents used and advents in the nose to brain drug delivery. [ABSTRACT FROM AUTHOR]