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Allergies Health Center

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Frequently Asked Questions About Allergies

Print these allergy questions and answers to discuss with your doctor.

What Types of Plants Produce the Most Allergy-Causing Pollen?

The type of pollen that most commonly causes allergy symptoms comes from plants (trees, grasses, and weeds) that typically do not bear fruit or flowers. These plants produce small, light, dry pollen granules in large quantities that can be carried through the air for miles.

Common plant allergens include:

  • Weeds, such as ragweed, sagebrush, redroot pigweed, lamb's quarters, goosefoot, tumbleweed (Russian thistle), and English plantain.
  • Grasses, such as timothy grass, Kentucky blue grass, Johnson grass, Bermuda grass, redtop grass, orchard grass, sweet vernal grass, perennial rye, salt grass, velvet grass, and fescue.
  • Hardwood deciduous trees, such as oak, ash, elm, birch, maple, alder, and hazel, as well as hickory, pecan, and box and mountain cedar. Juniper, cedar, cypress, and sequoia trees are also likely to cause allergy symptoms.

 

What Does a Pollen Count Mean?

A pollen count is the measure of the amount of pollen in the air. Pollen counts are commonly included in local weather reports and are usually reported for mold spores and three types of pollen: grasses, trees, and weeds. The count is reported as grains of pollen per square meter of air collected over 24 hours. This number represents the concentration of all the pollen in the air in a certain area at a specific time. The pollen count is translated into a corresponding level: absent, low, medium, or high.

In general, a "low" pollen count means that only people extremely sensitive to pollen will experience allergy symptoms. A "medium" count means many people who are relatively sensitive to pollen will experience allergy symptoms and a "high" count means most people with any sensitivity to pollen will experience allergy symptoms.

Although the pollen count is an approximate value and fluctuates, it is useful as a general guide when you are trying to determine whether or not you should stay indoors to avoid pollen contact.

Should I Consider Moving to Decrease My Allergy Symptoms?

No. Moving to a different geographic climate will not help "cure" allergies or allergy symptoms. Most people who relocate to get away from pollens that cause their allergies tend to find that they eventually develop allergies to the plant pollens in the new area.

How Can I Tell If My Child Has Allergies or a Common Cold?

Symptoms of allergies and colds can be similar, but here's how to tell the difference:

Occurrence of symptoms:

Both allergies and colds cause symptoms of sneezing, congestion, runny nose, watery eyes, fatigue, and headaches. However, colds often cause symptoms one at a time: first sneezing, then a runny nose, and then congestion. Allergies cause symptoms that occur all at once.

Duration of symptoms:

Cold symptoms generally last from seven to 10 days, whereas allergy symptoms continue as long as a person is exposed to the allergy-causing agent. Allergy symptoms may subside soon after elimination of allergen exposure.

Mucus discharge:

Colds may cause yellowish nasal discharge, suggesting an infectious cause. Allergies generally cause clear, thin, watery mucus discharge.

Sneezing:

Sneezing is a more common allergy symptom, especially when sneezing occurs two or three times in a row.

Time of year:

Colds are more common during the winter months, whereas allergies are more common in the spring through the fall, when plants are pollinating.

Presence of a fever:

Colds may be accompanied by a fever, but allergies are not usually associated with a fever.

WebMD Medical Reference

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