1.0 Introduction to Allergy
Our immune system is designed to protect us from harmful bacteria and viruses. However, sometimes it becomes "over-sensitive" and reacts to harmless substances like dust or pollen as if they were dangerous invaders. This hypersensitive reaction is called an Allergy.
Allergy: An exaggerated or hypersensitive response of the immune system to certain substances called allergens.
Allergen: Any substance that causes an allergic reaction.
Common Allergens
Allergens can enter our body through various routes. Common examples include:
- Dust & Pollen: From flowers, grass, or house dust.
- Food Items: Peanuts, milk, eggs, seafood, or gluten.
- Animal Dander: Tiny bits of skin or fur from pets.
- Drugs: Certain medications like Penicillin.
- Stings: From bees, wasps, or ants.
Common Symptoms
When an allergen enters the body, it triggers the release of a chemical called Histamine, which causes:
- Sneezing and a runny or stuffy nose.
- Itching and rashes on the skin (Hives).
- Redness or watering of the eyes.
- Swelling of the face, lips, or tongue.
- Shortness of breath or wheezing.
In rare cases, a severe allergic reaction can lead to Anaphylactic Shock. This is a life-threatening condition where the throat swells up and blood pressure drops. It requires immediate medical attention and an injection of Epinephrine (Adrenaline).
Allergies are often hereditary. If both your parents have allergies, there is a 75% chance that you might develop one too!
2.0 Types of Allergies and Routes of Entry
Allergies are often classified based on when they occur or how the allergen enters our body. Understanding these categories helps in avoiding triggers and managing symptoms effectively.
Classification by Occurrence
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1. Seasonal Allergies: These occur only at certain times of the year.
Example: Hay Fever, which is common in spring or autumn when plants release pollen. -
2. Perennial Allergies: these can occur year-round because the allergens are always present in the environment.
Example: Allergies to dust mites, pet dander, or certain indoor molds.
How Allergens Enter the Body
How Doctors Diagnose Allergies
If you have persistent symptoms, a doctor might perform:
- Skin Prick Test: A tiny amount of various allergens is placed on the skin to see if a red bump (wheal) appears.
- Blood Test: Measures the amount of IgE antibodies (Immunoglobulin E) in the blood.
- Elimination Diet: Removing suspected food items one by one to find the culprit.
In exams, if asked what causes the symptoms of allergy, the technical answer is Histamine. This is a chemical released by Mast Cells when they detect an allergen.
The medicines we take to treat mild allergies are called Antihistamines. As the name suggests, they work by blocking the action of histamine in the body!
3.0 Prevention and Precautions
While most allergies cannot be "cured" permanently, they can be managed effectively. The best way to deal with an allergy is a simple rule: Avoid the Trigger. By taking specific precautions, an allergic person can lead a perfectly normal and healthy life.
Practical Prevention Tips:
- For Dust/Pollen: Keep windows closed during high pollen seasons and use air purifiers. Use a damp cloth for dusting instead of a dry one to avoid spreading particles.
- For Food Allergies: Always read food labels carefully before buying or eating packaged items. Inform restaurant staff about your allergies.
- For Pet Allergies: Keep pets out of the bedroom and wash them regularly to reduce dander.
- Personal Hygiene: Wash your hands and face after coming from outdoors to remove any allergens stuck to your skin.
Treatment Options
If avoidance is not possible, the following medical treatments are common:
- Antihistamines: Drugs that block the action of histamine to reduce symptoms like itching and sneezing.
- Nasal Sprays: To reduce inflammation in the nose.
- Immunotherapy (Allergy Shots): Giving small, increasing doses of the allergen to "train" the immune system to stop overreacting.
People with severe allergies should always carry a Medical Alert Bracelet or an ID card that lists their triggers. This helps first responders provide the right treatment if the person becomes unconscious due to a reaction.
Many children actually outgrow their allergies as they get older! Allergies to milk and eggs often disappear by adulthood, though nut and seafood allergies usually last a lifetime.