Allergies / Allergic Rhinitis

What is an allergy?

Allergy is a genetic condition. When the body is exposed to substances (allergens) in our environment, those who are predisposed genetically to respond to these with exposure, will experience various symptoms of allergy depending on the target organ(s) involved. These range from mild or moderate discomfort (hay fever) to life threatening (asthma).

People suffer from hay fever when pollen is in the air; others develop skin rashes when they touch certain substances, some even experience stomach cramps after eating particular foods. All types of allergies can cause discomfort and can slow you down.

Who has allergies?

It is estimated that at least 20% of the population is likely to develop some kind of allergy, which means possibly more than 40 million Americans. It is most common for allergies to begin in childhood but symptoms can manifest themselves at any age. You are never too old to develop allergies! Allergies are a leading cause of school absenteeism and loss of productivity in the working world. Fortunately, the Allergy Center has a wide range of innovative testing and treatment techniques to make dealing with allergies easier than ever before.

Statistically, if one parent has allergies, then children will have a 25% chance of also developing allergies. Should both parents experience allergies, there is a 75%- 80% chance that their children will also have symptoms.

You may be at increased risk of developing an allergy if you:

  • Have a family history of asthma or allergies. You’re at increased risk of allergies if you have family members with asthma or allergies such as hay fever, hives or eczema.
  • Are a child. Although you can become allergic to something at any age, children are more likely to develop an allergy than are adults. Children sometimes outgrow allergic conditions as they get older. However, it’s not uncommon for allergies to go away and then come back sometime in the future.
  • Have asthma or an allergic condition. Having asthma increases your risk for developing an allergy. Also, having one type of allergic condition makes you more likely to be allergic to something else.

What are the most common allergens?

Primary examples of allergens are the pollens of trees, grasses and weeds, mold spores, dust mites, animal danders, drugs and insect venoms.

Dust mite allergies

Dust mite allergy is the allergic reaction to a certain dust mite protein. This reaction triggers inflammation in the lining of the nasal passages (allergic rhinitis) and lungs (asthma). It can also cause skin problems like eczema. Dust mite allergy can range from mild to severe. A mild case of dust mite allergy may cause occasional nasal congestion, watery eyes and sneezing. In severe cases, the condition is ongoing, or chronic, resulting in persistent sneezing, cough, congestion, facial pressure or severe asthma attack.

Ongoing (chronic) inflammation of tissues in the nasal passages caused by dust mite allergy can obstruct the sinuses, and may make you more likely to develop infections of the sinuses (sinusitis).

Dust mite allergies are present all year round, but may get worse at certain times of the year (fall in Northern California) and winter, when there is more exposure from being indoors more and using heavier bedding.

Dust mites, relatives of the spider, are too small to see without a microscope. Dust mites eat skin cells shed by people, and they thrive in warm, humid environments. In most homes, bedding, upholstered furniture and carpeting provide an ideal environment for dust mites.

The following factors increase your risk of developing a dust mite allergy:

  • Exposure. Being exposed to high levels of dust mites, especially early in life, increases your risk.
  • Age. You’re more likely to develop dust mite allergy during childhood or early adulthood.

Mold allergies

A respiratory mold allergy can occur when you breathe in mold spores. Like other respiratory allergies, mold allergy can make you cough, make your eyes itch and can cause recurrent cause nasal symptoms such as congestion and sneezing. In some people, mold allergy is linked to asthma and exposure causes restricted breathing and other airway symptoms.

If you have a mold allergy, the best defense is to reduce your exposure to the types of mold that cause your reaction. Mold allergy symptoms vary from person to person, and range from mild to severe. You may have year-round symptoms or symptoms that flare up only during certain times of the year (fall). You may notice symptoms when the weather is damp, or you’re in indoor or outdoor spaces that have high concentrations of mold.

Molds are very common both inside and outside. There are many different types, but only certain kinds of mold cause allergies. Being allergic to one type of mold doesn’t necessarily mean you’ll be allergic to another. Some of the most common molds that cause allergies include alternaria, aspergillus, cladosporium and penicillium.

If you are allergic to molds, your symptoms may be worse if you:

  • Work in an occupation that exposes you to mold. Occupations where mold exposure may be high include farming, dairy work, logging, baking, mill-work, carpentry, greenhouse work, wine-making and furniture repair.
  • Live in a house with high humidity. If your indoor humidity is higher than 50 percent, you may have increased exposure to mold in your home. Mold can grow virtually anywhere if the conditions are right — in basements, behind walls in framing, on soap-coated grout and other damp surfaces, in carpet pad and in the carpet itself. Exposure to high levels of household mold may trigger mold allergy symptoms.
  • Work or live in a building that’s been exposed to excess moisture. Leaky pipes, water seepage during rainstorms, flood damage: At some point, nearly every building has some kind of excessive moisture. This moisture can allow mold to flourish, along with other common allergens, including dust mites and cockroaches.
  • Live in a house with poor ventilation. Tight window and door seals may trap moisture indoors and prevent proper ventilation, creating ideal conditions for mold growth. Damp areas, such as bathrooms, kitchens and basements, are most vulnerable.

Allergic Rhinitis

There are two types of rhinitis: allergic rhinitis (sometimes called “hay fever”) and non-allergic rhinitis. With allergic rhinitis, the body produces IgE antibodies to certain substances you are allergic to, called allergens. When you come into contact with these allergens, IgE triggers the allergic reaction that causes the lining of the nose to become inflamed.

People who suffer from seasonal allergic rhinitis — known as hay fever — may be allergic to trees, grasses, weed pollens, or mold spores that are more common during a particular season of the year. Those who experience symptoms year-round, a condition called perennial allergic rhinitis, are usually allergic to dust mites, pet dander, mold spores, and/or foods.

If you can’t identify an allergen through allergy testing as the cause of the rhinitis, you probably have non-allergic rhinitis. One in three people with rhinitis don’t seem to have a specific allergen that triggers the problem.

Irritants such as cigarette smoke, odors, weather changes, and dust are common culprits for people with non-allergic rhinitis. Non-allergic rhinitis can also be caused by long-term use of nasal decongestant sprays. People who have non-allergic rhinitis usually suffer from their symptoms all year long.

Hay fever

Hay fever, causes cold-like symptoms such as a runny nose, itchy nose and roof of the mouth, nasal congestion, sneezing and sinus pressure. Watery or itchy eyes are often associated, as are swollen, blue-colored skin under the eyes (allergic shiners).

Hay fever is usually caused by outdoor or indoor airborne allergens, usually pollen or pet dander. Some people have hay fever year-round. For others, hay fever gets worse at certain times of the year, usually in the spring, summer or fall when there is plant pollination. One of the most common allergic conditions, hay fever affects about one in five people. Hay fever symptoms can interfere with day-to-day activities and have an impact on quality of life, including sleeplessness, fatigue, and irritability.

Is it hay fever? Or is it a cold?

Signs and symptoms can be different. Here’s how to tell which one’s causing your symptoms:

  • Hay Fever
  • Colds
  • Signs & Symptoms

    Runny nose with thin, watery discharge; no fever

    Runny nose with watery or thick yellow discharge; low-grade fever

  • Onset

    Immediately after exposure to allergens

    One to three days after exposure to cold virus

  • Duration

    As long as you’re exposed to allergens

    Five to seven days


Seasonal hay fever triggers include:

  • Tree pollen, common in the spring
  • Grass pollen, common in the late spring and summer
  • Weed pollen, common in the fall
  • Spores from fungi and molds, which can be worse during warm-weather months

Year-round hay fever triggers include:

  • Dust mites or cockroaches
  • Dander (dried skin flakes and saliva) from pets such as cats, dogs or birds
  • Cockroaches
  • Spores from indoor and outdoor fungi and molds

Hay fever doesn’t mean you’re allergic to hay. Despite its name, hay fever is almost never triggered by hay, and it doesn’t cause a fever.