1 of 5 / Overview
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What Is an Allergy?
This article explains the basics of an allergic reaction. Learn what happens when your immune system goes on high alert.
Who Gets Allergies?
Anyone can get them, at any age. You could develop them as a child, or you might not have any symptoms until you’re an adult.
What Causes an Allergic Reaction?
While your problem may seem to start in the nose or the eyes, allergies actually come from an immune system run wild.
Allergies and Asthma
Worsening of asthma symptoms can be triggered by allergies, which can temporarily increase the inflammation of the airways.
2 of 5 / Symptoms & Types
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Spring Allergies
There's no cure but you can take steps to curb springtime allergies, from medication to household habits.
Summer Allergies
Summer allergies are usually triggered by pollen from grasses and weeds.
Fall Allergies
Ragweed, mold, and dust mites are the biggest allergy triggers in the fall.
Winter Allergies
With indoor allergies such as mold and dust mites, you may notice symptoms more during winter, when you spend more time inside.
3 of 5 / Tests & Diagnosis
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Finding the Cause of Allergies
An allergist may be able to help identify your allergy triggers. Several different types of allergy tests are used to do this.
When to See an Allergist
If you think you have allergies, think about seeing a doctor who can tell you whether you do or not.
Allergy Skin Test
Skin testing is one way your doctor can check on what causes your allergy symptoms.
Blood Test for Allergies
Allergy blood tests detect and measure the amount of allergen-specific antibodies in your blood.
4 of 5 / Treatment
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Types of Allergy Drugs
Learn all about the different over-the-counter and prescription medicines that can help ease annoying symptoms.
What Are Antihistamines?
When medicine is needed to stem allergy symptoms, antihistamines are often first in line.
How Decongestants Work
When allergies make your nose stuffed up, an antihistamine generally won't help. But a decongestant might.
Nasal Sprays for Allergies
When allergies strike, nasal sprays can help. There are many different types, and most work faster than pills.
5 of 5 / Appointment Prep
View AllQuestions for Your Doctor About Chronic Sinusitis With Nasal Polyps
Whether you're newly diagnosed with chronic sinusitis with polyps or already in treatment, learn how to make the most of your doctor appointment.
Questions for Your Doctor About Your Child's Food Allergies
Whether your child is newly diagnosed with a food allergy or you have questions about their current management plan, learn how to make the most of your doctor appointment.
Suggested Reads about Allergies
Can Local Honey Help My Allergies?
Some say a spoonful of honey makes the sneezing and sniffling symptoms of pollen allergies go away. WebMD asked the experts.
Common Allergy Triggers
From pollen and pets to food and bugs, find out the most common things that can trigger allergy symptoms in this WebMD slideshow.
Common Plants and Trees That Trigger Allergies
Find out more from WebMD's slideshow about which plants and trees might be producing pollen that is causing your itchy eyes and a runny nose.
Food Allergy Triggers, Common and Uncommon
Peanuts, tomatoes, and even exercise, can bring on food allergies, some quite dangerous. This WebMD slideshow helps identify triggers, symptoms, and tests to help keep your family safe.
Top Search Terms for Allergies
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