Flonase is a nasal spray that contains corticosteroids to reduce swelling and inflammation caused by allergies. It can lower white blood cell count and should not be used by children under 4. Afrin is a decongestant nasal spray that shrinks blood vessels in the nose to relieve congestion from allergies or colds, but should only be used short-term to avoid rebound congestion or addiction. Robitussin contains an expectorant to loosen mucus from coughs and congestion but can cause side effects ranging from headaches to seizures.