Itch is the most common chief complaint in patients visiting
dermatology clinics and is analogous to cough and also sneeze of
the lower and upper respiratory tract, all three of which are host
actions trying to clear noxious stimuli. The pathomechanisms of
these symptoms are not completely determined. The itch can
originate from a variety of etiologies. Itch originates following the
activation of peripheral sensory nerve endings following damage
or exposure to inflammatory mediators. More than one sensory
nerve subtype is thought to subserve pruriceptive itch which
includes both unmyelinated C-fibers and thinly myelinated Aδ
nerve fibers. There are a lot of mediators capable of stimulating
these afferent nerves leading to itch. Cough and itch pathways are
mediated by small-diameter sensory fibers. These cough and itch
sensory fibers release neuropeptides upon activation, which leads
to inflammation of the nerves. The inflammation is involved in the
development of chronic conditions of itch and cough. The aim of
this review is to point out the role of sensory nerves in the
pathogenesis of cough and itching. The common aspects of itch
and cough could lead to new thoughts and perspectives in both
fields.