What Are Allergies and Why Do They Happen?

An allergy is an overreaction of the immune system to substances that are actually harmless, called allergens. When an allergen enters, the body produces IgE antibodies that trigger histamine release — the substance behind symptoms like itching, rashes, and swelling.

Heredity plays a major role: if one parent has a history of allergies, the child’s risk rises to 20-40 percent, and if both parents have allergies the risk reaches 60-80 percent. Environmental factors such as pollution, allergen exposure, and dietary changes also play a part.

Recognizing Allergy Symptoms

Mild to moderate allergy symptoms include sneezing, a stuffy or runny nose, red and itchy eyes, skin rashes, itching, and hives. Food allergies are commonly triggered by seafood, fish, nuts, eggs, and milk.

Watch for signs of a severe reaction (anaphylaxis): swelling of the lips or face, difficulty swallowing, shortness of breath, nausea and vomiting, or loss of consciousness. This condition is life-threatening and requires emergency medical care.

How to Manage Allergies

The main step in managing allergies is avoiding the triggering allergen. Note any foods, medications, or exposures that occur before symptoms appear so the trigger can be identified. If the cause is hard to pin down or symptoms keep recurring, consult a doctor for allergy testing.

To relieve symptoms, over-the-counter antihistamines can help reduce itching and rashes. A cold compress on the itchy area for 10-15 minutes also eases itching and swelling, and calamine lotion can soothe itchy skin. Avoid scratching too hard so irritation does not worsen.

When Should You See a Doctor?

See a doctor or health facility promptly if allergy symptoms do not improve, keep recurring, or disrupt daily activities. Doctors can prescribe medication matching the severity, such as corticosteroids.

Do not delay seeking medical help if signs of a severe reaction appear: shortness of breath, swelling of the face or throat, severe dizziness, or vomiting. In anaphylaxis cases, patients need an epinephrine injection as soon as possible.