The nasolacrimal duct is found in the nasolacrimal canal and formed by the maxilla and lacrimal bone.

The Nasolacrimal duct allows entry into the systemic circulation. If a medication will cause systemic effects, you will want to block the Nasolacrimal duct with gentle pressure.

The nasolacrimal duct carries excess tears into the nasal cavity. This is why you get a runny nose when you cry.

In animals, the nasolacrimal duct is a tear duct. This duct carries tears from the lacrimal sac to the nasal cavity.