Atrophic rhinitis is a chronic inflammatory disease characterized by atrophy of the nasal mucosa and turbinates. It is classified as primary or secondary. Primary atrophic rhinitis has no identifiable cause, while secondary is caused by infections, surgery, or nasal septal deviations. Symptoms include a fetid odor, crusting, and nasal obstruction. Treatment involves local and systemic antibiotics, steroids, irrigation, and surgical procedures like Young's operation to reduce nasal volume and crusts.