allergy
C2Pronunciation
UK
- /ˈælədʒi/
US
- /ˈælərdʒi/
Description
- hypersensitivity to allergens
- immune system overreaction
- allergic reaction
Imagine your body as a fortress protecting you from invaders like germs. Usually, it's great at identifying the real threats. But sometimes, it mistakes harmless things – like pollen, pet dander, or peanuts – for enemies! That mistaken identity is basically what an allergy is. It's not just a little dislike; it's your immune system overreacting and causing symptoms ranging from itchy eyes to serious breathing problems.
You might have an allergy to cats (meaning you react when around them), or develop an allergy after repeated exposure. Allergies aren't contagious, but they can be a real nuisance! Think of someone sneezing uncontrollably around flowers – that's likely an allergic reaction in action.
An allergy is a hypersensitivity disorder of the immune system. Essentially, it happens when your body mistakenly identifies a normally harmless substance—called an allergen—as dangerous. This triggers an immune response designed to fight off the perceived threat, even though there isn't one.
Allergens can be anything from pollen and dust mites to certain foods (like peanuts, shellfish, or milk), insect stings, medications, or even latex. The symptoms of an allergy vary widely depending on the allergen and the individual, ranging from mild reactions like sneezing, itchy eyes, skin rashes (hives), and a runny nose, to severe and potentially life-threatening responses called anaphylaxis—which can cause difficulty breathing, swelling, and a drop in blood pressure.
Allergies aren't always immediate. Typically, your immune system becomes sensitized after one or more exposures (often without you noticing). Then, the next time you encounter the allergen, you can have an allergic reaction. You might be allergic to something without even knowing it until you run into that trigger again.
People also use the word allergy loosely for anything that makes them feel unwell (like a food intolerance). But a true allergy involves the immune system and can sometimes be serious.
Doctors diagnose allergies through skin prick tests or blood tests. Treatment often involves avoiding the allergen whenever possible and using medications like antihistamines or epinephrine (for severe reactions) to manage symptoms. While there's no cure for allergies, many people can live full and active lives with proper management. So, if you consistently experience unusual reactions after exposure to certain substances, it's important to consult a doctor to determine if you have an allergy and how best to address it.
Examples
- 1
Food labels
I always read the ingredients carefully because I have a nut allergy.
- 2
Animal trigger
His allergy to cats makes his eyes itch within minutes.
Pattern
allergy to + trigger
allergy caused by that thing
- 3
Medical testing
The doctor sent her for tests to find out what was causing her allergies.
- 4
School information
Please let the school know if your child has any food allergies.
- 5
Seasonal allergy
In spring, my pollen allergy is so bad that I keep the windows closed.
- 6
Emergency medicine
She carries medicine with her in case her allergy causes a serious reaction.
Forms and spellings
2 forms open this card.
Main spelling
- allergynoun
Forms
- allergiespluralnoun