Tears are crucial to lubricate the eye and protect it from harmful debris. An excess of tearing can be due to dry, irritated eyes (reflex tearing), lower lids that are turned in or out, excess production of tears, or a problem in the tear drainage system. Tears normally drain through small holes in the inner corners of the eyelids called puncta. They then pass through the canalicular system, into the lacrimal sac, and through the nasolacrimal duct into the nose. A blockage at any portion in this pathway can lead to tears that overflow out of the eyelids and down the face. If the nasolacrimal duct is blocked, collection of tears in the lacrimal sac can lead to the development of a mucous discharge and can lead to painful infections called dacryocystitis.