Allergic rhinitis – Rhinitis is an inflammation of the lining of the nose and is caused by an allergy. Allergic rhinitis is sometimes referred to as hay fever or seasonal allergies.

Allergy shots – Allergy shots are used if you have more severe allergies that don’t clear with over-the-counter or prescription medications. Your health care provider officially calls allergy shots immunotherapy.

Antihistamines – This is a drug used to treat allergies that works to reduce the effects of histamine in your body.

Anti-inflammatory medication – This type of medication is used to reduce inflammation that causes itchy, stuffy nose or itchy eyes.

Dander – See pet dander.

Decongestants – Decongestants reduce blood flow to the nose, eyes or ears, which allows less fluid in the area, clearing up congestion and symptoms of stuffy nose and difficult breathing.

Dust mite – A dust mite is a microscopic animal commonly found in American homes that can cause local irritation and itching.

First generation antihistamines – First generation antihistamines treat allergies by blocking the action of histamine, a substance produced by your body in response to an allergen, causing your allergic symptoms. They are available over the counter and may cause drowsiness.

Hay fever – Hay fever is a type of allergic rhinitis, with symptoms of sneezing, runny or stuffy nose and watery eyes that occurs seasonally from exposure to pollen.

Histamine – The chemical released in your body during an allergic response is called histamine.

Immunotherapy – See allergy shots.

Mold spores – Mold spores are “seeds” released by molds that can trigger your allergic reactions. There are thousands of types of molds.

Over the counter (OTC) – This identifies those drugs that are sold without a prescription in grocery stores, pharmacies or retail stores.

Pet dander – Dead skin, or dander, from pets can cause allergic reactions in some people.

Pollen – Plants produce microscopic round or oval grains to reproduce that are called pollen, which can cause allergic reactions in some people.

Prescription – A prescription is a written order for medication, therapy or a device given by your health care provider.

Second generation antihistamines – Second generation antihistamines, like Alavert™ and Claritin^®, treat allergies by blocking the action of histamine, the substance that causes your symptoms. Loratadine, one such antihistamine, is now available over the counter. Unlike first generation antihistamines, they are not as likely to cause drowsiness.