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Allergy and Antihistamine Information Frequently Asked Antihistamine Questions What is the
What is the
Decongestants are useful in reducing the swelling within the nose but they are not intended for use over an extended period of time. If you use them for more than three days in a row, you may develop what is known as the "rebound effect" which can make nasal swelling even worse. Increasing the dosage or using the spray more frequently in response to this can lead to a condition called "rhinitis medicamentosa", where a sufferer alternates between decongestion and rebound swelling.