Cause

Allergic rhinitis, often called hay fever, occurs when your immune system overreacts to particles in the air that you breathe—you are allergic to them. Your immune system causes symptoms such as sneezing and a runny nose. The particles are called allergens, which simply means they can cause an allergic reaction.

Several types of allergens cause allergic rhinitis, including pollens, mold, dust mites, animal dander, and cockroaches. Although polluted air is not an allergen, it can irritate your nose and lungs. An irritated nose or lungs may make an allergic reaction more likely when you breathe in an allergen.

Symptoms

Symptoms of allergic rhinitis may develop within minutes or hours after you breathe in an allergen. The symptoms can last for days.

Symptoms that often start as soon as you breathe in an allergen include:

• Sneezing over and over again, especially after you wake up in the morning.
• A runny nose.
• A tickle in your throat or coughing caused by postnasal drip.
• Watery, itchy eyes. This may be allergic pinkeye.
• Itchy ears, nose, and throat.

Other symptoms that may take longer to appear include:

• A stuffy nose, possibly with sniffing. This is the most common symptom in children.
• Breathing through your mouth because your nose is blocked.
• Rubbing your nose. Children tend to do this.
• Eyes being sensitive to light.
• Feeling tired, grumpy, or moody.
• Not sleeping well.
• A long-lasting (chronic) cough.
• Pressure in your ear or having a hard time hearing.
• Discomfort or pain in your face.
• Dark circles or patches under your eyes (allergic shiners).

Other problems with symptoms similar to allergic rhinitis include upper respiratory infections (URIs), nasal defects, and inflammation (rhinitis) not caused by an allergen (nonallergic rhinitis).

When symptoms may change

Your symptoms may be better or worse at different times of the year or different times in your life. For example:

• If you are allergic to dust mites, animal dander, or indoor mold, your symptoms may be more severe in winter when you spend more time indoors.
• If you have a pollen allergy, your symptoms may vary based on what plants grow in your area and what season it is.
• If you get pregnant, your symptoms might get worse. Allergic rhinitis can then make asthma and sinusitis worse.

• As you grow older, allergens may affect you less.