The purpose of this guidance is to assist applicants of new drug applications and biologics license applications in developing drug products for the treatment of nonallergic rhinitis (NAR) in children and adults. The guidance discusses issues regarding the definition of a clinical phenotype, trial design, efficacy, and safety for new drug products under development. In particular, the guidance addresses development programs for the treatment of vasomotor rhinitis (VMR), which is a subtype of NAR.