Infographic with allergy facts
What you need to know about

Urticaria (hives)

What are urticaria (hives)?

  • Red, swollen, itchy bumps or wheals that can vary from small to large lesions and cover extensive areas of the body
  • A clinical reaction, not a disease
  • Formed when the body’s mast cells release a chemical called histamine as part of an allergic or hypersensitive reaction


Acute – when hives have been present for less than six weeks

  • Estimated occurrence is 15-24% of U.S. population at some time in their lives
  • More likely in younger populations
  • Involves intensely itchy hives and possible swelling or angioedema (reaction in deeper levels of skin)
  • Angioedema involving upper respiratory tract can lead to airway obstruction and emergency intervention

Chronic – hives present for longer than six weeks

  • More common in adults than children
  • About 20% of patients have hives 10 years or longer
  • Causes and triggers include autoimmune diseases, chronic infections, dental abscess, chronic sinusitis, chronic parasitic infections and physical factors such as pressure, cold, sunlight or heat.

Idiopathic – hives with no known cause


  • Food allergy – Most common foods associated with hives, which appear within 90 minutes after ingesting trigger foods, are peanuts, tree nuts, milk, egg and fish. Random screening for food allergy without a history of reactions is costly and not recommended.
  • Drug allergy Almost any medication can cause hives, including prescription and over-the-counter drugs, supplements, herbs and vitamins.
  • Insect stings Sensitivity to insect bites or stings can leave patients with localized hives that may remain for days.
  • Latex allergy
  • Animal allergy
  • Mold allergy
  • Infection – Includes viral, mycoplasma, fungal and parasitic infections. Sometimes hives occur after obvious symptoms of infection have resolved.
  • Solar – Usually occurs within minutes following sunlight exposure
  • Cold – Appears when skin is warmed after exposure to cold
  • Cholinergic – Results from physical activity, increased temperature and emotional stimuli
  • Dermatographism – Reaction affecting 5% of population that occurs after firmly stroking or scratching the skin


  • Allergists conduct a thorough medical history and exam and may perform skin testing, blood work or challenges.
  • Diagnosis can be quite challenging, and patients often go from one physician to another in hopes of identifying the cause.


  • Identify and eliminate the cause if possible.
  • Antihistamines work best if taken on regular basis for defined period to suppress hives.
  • Corticosteroids may be used for short periods of time for severe cases.
  • We have found Xolair, an injectable prescription medication, to be very helpful in treating stubborn cases of chronic, idiopathic urticaria.

What you need to know about

Atopic dermatitis

What is atopic dermatitis (AD)?

  • Skin condition that often affects people with asthma and/or hay fever or with family members who have these conditions
  • Also known as eczema
  • Inherited from parents and almost always begins in childhood, usually during infancy
  • Tends to improve and worsen periodically.

Signs and symptoms

Eczema on the torso of an adult.

Eczema on the face of an infant.

  • Typical symptoms of atopic dermatitis include dry, scaly skin and intense itching.
  • Skin may become thickened from long-term scratching and rubbing.
  • During flares, open weeping or crusted sores may develop from scratching and/or infection.


Avoid triggers
  • Since allergic reactions to food or environmental factors can trigger flares, we recommend allergy skin testing. (Read more about allergy skin testing) As many as three of every 10 children with AD suffer from food allergies, especially those under age 2.
  • Minimize exposure to irritants and allergens that may trigger atopic dermatitisAD.
During flares
  • Use lukewarm water; hot showers strip natural oils from skin and trigger itch.
  • Use only gentle cleansers such as Dove, Oil of Olay, Cetaphil, Basis, Aveeno, CeraVe or Neutrogena. Sensitive-skin formulas are recommended.
  • Apply moisturizer to skin within three minutes after bathing. Cetaphil cream, Eucerin, Advanced Therapy Lubriderm, Moisturel, Aquaphor, CeraVe, Acid Mantle and Cutemol cream are often recommended and should be applied once or twice daily.
  • Trim fingernails.
  • Avoid activities causing excessive sweating.
  • Dress in clothes that breathe such as 100% cotton or soft fabrics.
  • Avoid wools, nylon or harsh fabrics.
  • Avoid bleach or fabric softeners that can leave residue on clothing. Use extra rinse cycle.
  • Use humidifiers with ideal settings of 35-40% to increase amount of moisture in your home. Keep home thermostat low.


Topical steroids
  • May be necessary if skin becomes inflamed.
  • Seven groups – Group I is strongest; Group VII is mildest. In general, mildest steroids that are effective should be used.
  • Ointments are greasier than creams and penetrate skin more easily, possibly increasing effectiveness.
  • Side effects including skin thinning, stretch marks or spider veins (especially on face) are more likely if high-potency steroids are used. Long-term use raises risk of side effects.
Non-steroid options
  • Anti-inflammatory medications such as tacrolimus (Protopic), pimecrolimus (Elidel) and EpiCeram can relieve itching and redness and can be used for short or long periods as needed.
  • Possible side effects include burning or feeling of warmth at site of application.
  • Antibiotics may be prescribed to treat accompanying skin infections.
  • Antihistamines may help control itchiness.
  • Biological drugs show great promise in providing relief for certain patients.

What you need to know about

Contact dermatitis

What is contact dermatitis?

  • Skin condition resulting from exposure to something you’re sensitive or allergic to
  • Common irritants or allergens that can cause contact dermatitis include:
  • Poison ivy
  • Jewelry made of certain metals (especially nickel or gold)
  • Sunscreen
  • Fragrant soaps
  • Rubber
  • Certain deodorants
  • Bleach
  • Hand sanitizers

Signs and symptoms

  • Red, irritated skin
  • Itching
  • Swelling
  • Bumps or blisters, sometimes filled with clear fluid
  • Hot or tender skin

Symptoms can range from mild to severe and can appear anywhere from a few hours to 10 days after coming into contact with the irritant or allergen. A contact dermatitis rash cannot be spread to anyone else.

Diagnosis and testing

  • Talk to your allergist to determine what caused the reaction so you can avoid that allergen or irritant in the future.
  • Record your activities and items that led to a reaction. If you’re unsure, simply list anything that may have touched your skin within two days of symptoms.
  • A patch test can determine potential causes, such as rubber, fragrances or hair dye. Patients are typically asked to wear patch for 48 hours before returning to allergist one day after patches are removed and again a week later.


If you’ve come into contact with a potential allergen or irritant:

  • Immediately wash affected area with soap and water.
  • Prescription creams, oral medication, antihistamines and ointments may provide relief from itching and heal damaged skin.
  • Avoid scratching affected area to prevent infection.

Photoallergic contact dermatitis

Photoallergic contact dermatitis occurs when an irritant or allergen causes a reaction only after being exposed to the sun. This condition can occur with sunscreens, shaving lotion and some perfumes. Patch testing performed by allergist can help identify products that cause this reaction.