Clinical Definition

A decongestant is a medication that causes vasoconstriction of the blood vessels lining the nasal cavity or sinuses. This action may reduce tissue swelling and decrease congestion in the nose. Due to their vasoconstriction action, decongestants may cause hypertension as a side effect.

In Our Own Words

Decongestants are used to treat nasal or sinus congestion and fullness. A stuffy or congested nose is often due to swelling of the blood vessels inside the nose. Decongestants work by shrinking the blood vessels inside the nasal membranes, helping to keep the passages more open. Decongestants are available by prescription and over the counter and are usually administered either orally or through a nasal spray.