Nasal decongestants work by constricting the dilated blood vessels in the nasal mucosa. The nasal membranes are effectively shrunk, so drainage of mucus and breathing are improved while the feeling of nasal stuffiness is relieved. The decongestant effects of topical products containing oxymetazoline or xylometazoline are longer lasting (up to 6 hours) than those of some other preparations e.g. ephedrine or phenylephrine.