An allergy is when your immune system reacts to a foreign substance, called an allergen. It could be something you eat, inhale into your lungs, inject into your body or touch. This reaction could cause coughing, sneezing, hives, rashes, itchy eyes, a runny nose and a scratchy throat. In severe cases, it can cause low blood pressure, breathing trouble, asthma attacks and even death.
There is no cure for allergies. You can manage allergies with prevention and treatment. More Americans than ever say they manage allergies. It is among the country’s most common, but overlooked, diseases.
Types of indoor and outdoor allergies include sinus swelling, seasonal and returning allergies, hay fever and nasal allergies. Many people with allergies often have more than one type of allergy. The most common indoor/outdoor allergy triggers are: tree, grass and weed pollen, mold spores, dust mites, cockroaches, and cat, dog and rodent dander.
Skin allergies include skin inflammation, eczema, hives, chronic hives and contact allergies. Plants like poison ivy, poison oak and poison sumac are the most common skin allergy triggers. But skin contact with cockroaches and dust mites, certain foods or latex may also cause skin allergy symptoms.
Eight foods cause most food allergy reactions. They are milk, soy, eggs, wheat, peanuts, tree nuts, fish and shellfish.
People who have insect allergies are often allergic to bee and wasp stings and poisonous ant bites. Cockroaches and dust mites may also cause nasal or skin allergy symptoms.
Updated April 2021.
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