Allergies

When you have allergies, your immune system makes antibodies that identify a particular allergen as harmful. When you come into contact with the allergen, your immune system's reaction can inflame your skin, sinuses, airways, or digestive system.

The severity of allergies varies from person to person and can range from minor irritation to anaphylaxis — a potentially life-threatening emergency. While most allergies can't be cured, treatments can help relieve your allergy symptoms.

Allergies are among the most common chronic conditions worldwide. The tendency to develop allergies is often hereditary, which means it can be passed down through genes from parents to their children. However, not everyone in a family will necessarily have allergies.

Allergy symptoms depend on the substance involved and can involve the airways, sinuses and nasal passages, skin, and digestive system. Reactions can range from mild to severe.

Respiratory Symptoms

• Cough - often dry and persistent
• Sneezing and runny nose
• Nasal congestion
• Postnasal drip
• Wheezing or shortness of breath
• Chest tightness

Skin Symptoms

• Skin rash or hives
• Itching of skin
• Skin swelling
• Eczema or atopic dermatitis
• Abnormal appearing skin
• Redness and warmth

Eye Symptoms

• Itchiness of eye
• Swollen eye or eyelids
• Red, watery eyes
• Dark circles under eyes (allergic shiners)

Swelling and Edema

• Lip swelling
• Tongue or throat swelling
• Peripheral edema
• Fluid retention
• Facial swelling

Severe Symptoms (Anaphylaxis)

• Difficulty breathing
• Rapid pulse
• Drop in blood pressure
• Loss of consciousness
• Severe swelling of face and throat
• Skin reactions including hives and flushing

Airborne Allergens

• Pollen: Trees, grasses, and weeds
• Dust mites: Tiny organisms in household dust
• Mold: Indoor and outdoor mold spores
• Pet dander: Skin flakes from cats, dogs, and other animals
• Cockroach droppings: Common in urban areas

Food Allergens

• Peanuts and tree nuts
• Milk and dairy products
• Eggs
• Wheat and gluten
• Soy
• Fish and shellfish
• Sesame

Other Common Allergens

• Insect stings: Bees, wasps, hornets, fire ants
• Medications: Penicillin, aspirin, NSAIDs
• Latex: Natural rubber latex in gloves and medical devices
• Metals: Nickel, cobalt, chromium
• Fragrances: Perfumes and scented products
• Preservatives: In foods and cosmetics

You might be more likely to develop an allergy if you:

• Have a family history: Allergies, asthma, or eczema in parents or siblings
• Are a child: Children are more likely to develop allergies than adults
• Have asthma: Increases likelihood of developing allergies
• Have another allergy: Having one allergy increases risk for others
• Limited early exposure: Lack of early childhood exposure to germs (hygiene hypothesis)
• Born via C-section: May have higher allergy risk
• Formula-fed: Breastfeeding may provide some protection

To evaluate whether you have an allergy, your doctor will likely:

Medical History

• Ask detailed questions about symptoms
• Review family history of allergies
• Discuss timing and triggers of reactions
• Review medications and diet

Allergy Tests

• Skin prick test: Small amounts of allergens pricked into skin
• Intradermal test: Small amount injected under skin
• Patch test: Allergens taped to skin for 48 hours
• Blood test (IgE): Measures allergen-specific antibodies
• Elimination diet: For suspected food allergies
• Challenge test: Controlled exposure under medical supervision

Allergy treatment involves avoiding allergens, medications to reduce symptoms, and sometimes immunotherapy to reduce sensitivity.

Medications

Antihistamines

• Block histamine release
• Available OTC and prescription
• Options: cetirizine, loratadine, fexofenadine
• Help with sneezing, itching, runny nose

Decongestants

• Reduce nasal congestion
• Available as pills, liquids, nasal sprays
• Short-term use recommended
• May raise blood pressure

Corticosteroids

• Reduce inflammation
• Nasal sprays for allergic rhinitis
• Inhalers for asthma
• Topical creams for skin reactions

Other Medications

• Leukotriene modifiers: Block inflammatory chemicals
• Mast cell stabilizers: Prevent histamine release
• Immunomodulators: For severe eczema
• Epinephrine: Emergency treatment for anaphylaxis

Immunotherapy

• Allergy shots: Regular injections of allergens
• Sublingual tablets: Under-tongue allergen tablets
• Duration: Usually 3-5 years
• Goal: Reduce sensitivity to allergens
• Effectiveness: Can provide long-lasting relief

For Children

• Breastfeed if possible for at least 4-6 months
• Introduce allergenic foods early (4-6 months)
• Don't overly restrict diet during pregnancy
• Avoid tobacco smoke exposure
• Consider probiotics

General Prevention

• Identify and avoid triggers
• Read food labels carefully
• Inform restaurants about food allergies
• Be cautious with new medications
• Test new cosmetics on small skin area
• Maintain clean, low-allergen environment

Daily Management Tips

• Keep allergy medications readily available
• Monitor pollen and mold counts
• Plan activities around allergy triggers
• Communicate allergies to others
• Keep an allergy diary
• Regular follow-ups with allergist

Travel Considerations

• Pack extra medications
• Research destination allergens
• Bring allergy-friendly snacks
• Learn key phrases in local language
• Carry medical documentation
• Research nearby medical facilities

See your doctor if:

• OTC medications don't control symptoms
• Allergies interfere with daily activities
• You experience wheezing or difficulty breathing
• Symptoms worsen over time
• You develop new allergies
• You need allergy testing
• You're interested in immunotherapy