Research Highlight

Delivering antidepressants to brain through nose

doi:10.1038/nindia.2012.79 Published online 21 May 2012

Researchers have developed a new way to deliver antidepressants to the brain. They have used chitosan nanoparticles to ferry the antidepressant venlafaxine (VLF) through the nose. This technique will enhance the uptake of VLF to the brain through the nasal passage.

Besides depression, VLF extended-release capsules are also used to treat generalized anxiety, social anxiety and panic disorders. The blood–brain barrier (BBB) poses a problem for drugs that must reach the brain by crossing the BBB. This reduces the bioavailability of VLF in the brain, making it extremely difficult to treat common brain disorders such as depression.

In an attempt to increase its efficacy, the researchers loaded VLF into chitosan nanoparticles. They performed drug-release studies and explored the nanoparticles' ability to deliver VLF intranasally to the brain in depressed rats.

The VLF-loaded chitosan nanoparticles exhibited a higher drug transport efficiency and direct transport percentage than other formulations. The researchers used confocal laser scanning microscopy and the marker molecule rhodamine-123 to investigate the localization of chitosan nanoparticles in the brain and other organs.

The high drug targeting efficiency and nose-to-brain direct transport percentage of these VLF-loaded chitosan nanoparticles suggests excellent brain-targeting efficiency. The researchers say that these could be a promising approach for the nose-to-brain delivery of VLF.


  1. Haque, S. et al. Venlafaxine loaded chitosan NPs for brain targeting: pharmacokinetic and pharmacodynamic evaluation. Carbohydr. Polymer. 89, 72–79 (2012)