Allergies happen when your body thinks that harmless substances, like pet dander or peanuts, are actually pathogens that could make you sick. When this happens, your body prompts an immune response - which causes the symptoms like itchy eyes, itchy or runny nose, and scratchy throat that make allergic reactions troublesome.
There is a wide range of things that can cause an allergy as well as a wide range of reactions you can get as a result. You may get hives from a drug allergy, an itchy tongue from a food allergy, sneezing from a pet allergy, or a cough from a mold allergy. Allergy triggers can come in many forms such as airborne particles like pollen or dust, or as a result of a sting.
Allergic reactions are one of the most common conditions allergists treat. These usually occur in the eyes, nose, throat, sinuses, lungs, and skin. Another common condition is hay fever (allergic rhinitis), which refers to allergic reactions that cause a runny nose, watery eyes, sneezing, and itchy throat. These reactions are usually caused by an allergen like pollen, dust, or mold.
While many conditions like hay fever are the result of seasonal allergies and occur during certain times of the year, perennial allergies occur year-round. Asthma, for example, occurs when the airways in your lungs swell and inflame, which causes excess mucus and makes it hard to breathe. Allergens and irritants can also cause skin reactions like eczema (dermatitis) and hives.