Allergies: Questions & Answers
How can I tell if I have allergies or just 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 congestion. Allergies cause symptoms that occur all at once.
- Duration of symptoms -- Cold symptoms generally last 7 to 10 days, whereas allergy symptoms continue with exposure to the allergen (symptom trigger). 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 -- This is a more common symptom of allergies, especially when sneezing two or three times in a row.
- Time of year -- Colds more typically occur during the winter months, whereas seasonal allergies are more common in the spring through the fall, when trees, plants, and grasses are pollinating. Indoor allergies can affect individuals year-round.
- Presence of a fever -- Colds may be accompanied by a fever, but allergies are not usually associated with a fever.
What types of plants produce the most allergenic pollen?
The type of pollen that most commonly causes allergic reactions 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 allergenic culprits include:
- Weeds such as ragweed (including the marsh-elder, desert broom, feverfew, dog fennel, chamomile, chrysanthemum and marigold families), 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, hazel, hickory, pecan, box, and mountain cedar. Juniper, cedar, cypress, and sequoia trees also are likely to cause allergies.
What does a pollen count mean?
A pollen count is a measure of the amount of pollen in the air. Pollen counts are frequently included in local weather reports. The counts usually are 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 who are extremely sensitive to pollen will experience symptoms. A "medium" count means many people who are sensitive to pollen will experience symptoms, and a "high" count means most people with any sensitivity to pollen will experience symptoms.
Although the pollen count is approximate and fluctuates, it is useful as a general guide when you are trying to determine whether you should stay indoors to avoid pollen contact.
Should I consider moving to decrease my allergy symptoms?
No. It is a fallacy that moving to a different geographic climate will help "cure" allergies. 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. Other airborne indoor allergens, such as dust or mold, can cause symptoms in many different locations.
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This information is provided by the Cleveland Clinic and is not intended to replace the medical advice of your doctor or health care provider. Please consult your health care provider for advice about a specific medical condition. This document was last reviewed on: 12/27/2012...#8632