histamine

Histamine is an organic nitrogen compound that acts as a neurotransmitter and is involved in local immune responses, such as the inflammatory response. It allows capillaries to allow more white blood cells and certain proteins through to combat pathogens in infected tissues. While combatting these pathogens, histamine could cause some effects on the nasal mucous membrane such as sneezing and watery eyes. Histamine also have a role in sleep regulation, sexual responses, and a suppressive effect on neurons.