What is a potential side effect of prolonged use of a topical decongestant?

Prolonged use of a topical decongestant can lead to rebound congestion, a condition in which nasal passages become congested again after the medication is stopped. This occurs because the body's nasal tissues can become dependent on the medication to keep the blood vessels constricted. When the medication is no longer used, the blood vessels dilate, leading to increased blood flow and nasal swelling, causing more severe congestion than before the treatment started. This effect is particularly associated with over-the-counter nasal sprays that contain active ingredients like oxymetazoline or phenylephrine.

Understanding how rebound congestion occurs is important for patients using these drugs, as it can lead to a cycle of overuse, making the initial problem worse. In contrast to rebound congestion, side effects such as dry mouth, increased heart rate, and headaches are not typically linked to topical decongestants but may be associated with systemic decongestants or other medications. Therefore, recognizing rebound congestion as a side effect of prolonged use highlights the need for responsible use of topical decongestants.