Formulation considerations for improving intranasal delivery of CNS acting therapeutics

One of the principal impediments for the treatment of neurological conditions is the lack of ability of most of the medicinal agents to evade the blood-brain barrier. Among all the novel approaches to bypass the blood-brain barrier, nose to brain transport is the most patient compliant, non-invasive and effective approach. It directly transports drugs to the CNS via the trigeminal and olfactory nerves present in the nasal cavity. This review article focuses on anatomy and physiology of nasal cavity, potential of intranasal drug delivery, mechanisms of drug transport to brain, its advantages and limitations, novel intranasal formulations, marketed products, factors affecting nose to brain transport, formulation consideration of intranasal products and the future perspectives of CNS targeting via intranasal drug administration.