Allergy: What is Allergy? Causes, Symptoms, Types, Reaction, Treatment and Management

A medical disease known as an Allergy occurs when the body’s immune system responds improperly to a foreign chemical. An allergen is the substance responsible for the allergy. Allergies are your body’s reaction to normally nontoxic substances. Allergy symptoms range from mild to life-threatening. The common allergic disorders in India comprise allergic rhinitis, insect allergy, Urticaria, Eczema, Decongestants, nasal steroids, Antihistamines, Asthma medicines and Immunotherapy. Since the previous few decades, allergic disorders have significantly increased in prevalence, impacting 20% to 30% of India’s total population.

What are Allergies?

Allergies happen when your body’s immune system reacts to a food or substance that typically doesn’t elicit a reaction in most individuals, such as pollen, bee venom or pet dander. Antibodies are substances that are produced by your immune system. Your immune system produces antibodies that label a specific allergen as hazardous even when it is not when you have allergies. When you come into contact with the allergen, your immune system’s reaction can inflame your skin, airways, sinuses or digestive system. The severity of allergies varies from person to person and can range from slight irritability to anaphylaxis, a potentially life-threatening emergency. Some therapies can make you feel better even though most allergies cannot be cured. 

Causes of Allergy

The development of the allergy is influenced by a combination of genetic and environmental factors. 

• Genetic predisposition

• Environmental factors: A broad range of allergens have been found in India owing to diverse vegetation, climatic variation and different food habits
  • The allergic reaction may be brought on by exposure to allergens or irritants.
    • Dust mite droppings
    • Animal dander
    • Fungal spores
    • Pollens grains
    • Latex 
    • Insect sting/bites
  • Diet
  • Medications
  • Pollutant
    • Exhaust fumes
    • Tobacco smoke
  • Exposure to microorganisms (bacteria and viruses) during childhood

The main routes for allergen exposure in India are:

• Inhalation (airborne pollen grains trigger asthma)
• Ingestion (food allergy)
• Contact (contact dermatitis)

Symptoms of Allergy 

An allergic reaction can range in severity from moderate to severe. Different allergies cause different reactions in the body. The following are typical signs and symptoms of an allergic reaction: 

• Watery eyes
• Stomach ache
• Vomiting
• Sneezing
• Itchy skin, rash, hives
• Swelling in body parts exposed to the allergen
• Difficulty in breathing

An extreme case of allergy that necessitates prompt medical attention is Anaphylaxis which causes swelling and fainting of the lips, tongue and throat. 

Types of Allergy 

An allergy occurs when your body’s immune system sees a certain substance as dangerous. It reacts by causing an allergic reaction. There are several types of allergies. Some allergies are year-round and some are seasonal. While some allergies may be long-life. 

• Food allergy: It is an allergic response to a food or food ingredients. Common foods that cause allergies are Legumes (black gram, Kidney beans), Eggplant, Seafood (Prawns), milk and egg. 
• Skin allergy: 
  • Eczema: Allergic reactions and food exposure cause itchy, dry, and red skin.
  • Contact Dermatitis: An allergic reaction due to contact of skin with an irritant or an allergen may cause a blister, itching, red rash, scaling, cracking and burning.
  • Hives (Urticaria): Raised itchy bumps on the skin due to insect bites, food, medications
  • Angioedema: Swellings of the skin’s deep layers as a result of allergic reactions to certain medicines, foods or insect bites. 
• Dust allergy: Allergy due to pollen grains, dust motes, fungal spores or animal dander.
• Insect allergy: Allergy brought on by mosquito bites, bedbug stings, bee and wasp bites.
• Drug allergy: Allergic reaction following consumption of medication in liquid, tablet or injectable form. 
• Allergic rhinitis (hay fever): Allergies to airborne pollen grains, dust mites, animal fur and fungi can cause seasonal (during pollen season) or perennial (all year) allergic rhinitis. 

What is an Allergic Reaction?

An allergic reaction is the way your body responds to an allergen. When you come into touch with an allergen for the first time or if you have allergies, your body will manufacture Immunoglobulin E IgE. Your immune system makes antibodies to form IGE. The mucus membrane in the hollow organs that link one another from your mouth to your anus (Gastrointestinal or GI tract) contains IgG antibodies that attach to mast cells (allergy cells) that reside in your skin, respiratory tract (airways) and skin. Allergic reactions are sensitivities to substances called allergens that come into contact with the nose, eyes, skin, respiratory tract and gastrointestinal tract. They can be breathed into the swallowed lungs or injected. 

How are Allergies Treated?

Eliminating allergens is a crucial therapy strategy. Although frequently it doesn’t entirely stop allergic reactions. A further option for treating your allergies is to take over-the-counter and prescription allergy drugs. These may include:

• Antihistamines

• • • Fexofenadine
    • Cetirizine
    • Loratadine 
  • Nasal sprays: These medications are highly safe to take every day and quite effective, although it could take them up to a week to start working.
    • Cromolyn Sodium
    • Fluticasone nasal spray
    • Antihistamine nasal sprays
  • Decongestants: These drugs should be taken with caution when treating allergies, due to their more severe side effects and potential risks from prolonged use.
    • Phenylephrine 
    • Oxymetazoline
    • Pseudoephedrine

• Asthma medications

• • Inhaled steroids
  • Inhaled or oral bronchodilators
  • Injected drugs including Dupilumab, Omalizumab or Benralizumab
  • Oral Antileukotriened including Zafirlukast, Zileuton and Montelukast

Immunotherapy: If avoiding allergens and using over-the-counter and prescription drugs are not enough to control your allergy symptoms, Dr. Sheetu Singh may recommend Immunotherapy (allergy shots) or Sublingual Immunotherapy. Your healthcare professional will gradually increase the dosage over several months while exposing you to modest amounts of allergens.