allergy

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.