Nasal decongestant: A drug that shrinks the swollen membranes in the nose, making it easier to breathe. Decongestants can be taken orally or as nasal drops or spray. Nasal decongestants should not be used for more than 5 days in a row without a physician's consent. When nasal decongestants are used for a long time and then discontinued, symptoms often worsen (a rebound effect) because the tissues become dependent on the medication.
Reviewed on 6/3/2021