The intranasal route is the route of administration of a drug through the nose, including nose drops or other medications. Some drugs have a higher rate of absorption, and are thus more effective in smaller doses, through this route. It has been suggested that Blockbuster drug be merged into this article or section. ... For the article about nose in humans, see human nose. ...

The intranasal route may allow certain drugs and other molecules to bypass the blood-brain barrier via diffusion or axonal transport along olfactory and trigeminal nerves.^[1] The blood-brain barrier (BBB) is a membranic structure that acts primarily to protect the brain from chemicals in the blood, while still allowing essential metabolic function. ... This article does not cite any references or sources. ... Dynein, a motor protein responsible for retrograde axonal transport, carries vesicles and other cellular products toward the cell bodies of neurons. ... The olfactory nerve is the first of twelve cranial nerves. ... The trigeminal nerve is the fifth (V) cranial nerve, and carries sensory information from most of the face, as well as motor supply to the muscles of mastication (the muscles enabling chewing), tensor tympani (in the middle ear), and other muscles in the floor of the mouth, such as the...