Ever wonder why you feel better on some days than others? Experts say weather conditions can affect the amount of pollen and mold spores in the air at any given time. Allergy symptoms are often minimal on days that are rainy, cloudy or windless because pollen and mold spores do not move about during these conditions. Hot, dry and windy weather signals greater pollen and mold spore distribution and thus increases allergy symptoms.
All plants can cause seasonal allergies, but pollens from plants with bright flowers, such as roses, daffodils or daisies, usually do not trigger allergies. These plants have large, waxy pollens too heavy to be carried by the wind.
On the other hand, many trees, grasses and low-growing weeds have small, light and dry pollens that are easily carried by the wind. Some of the major plants that cause allergic reactions are: trees, such as oak, elm, birch, ash, hickory, poplar, sycamore, maple, cypress, walnut and western red cedar; grasses such as timothy, Bermuda, orchard, red top and sweet vernal; and weeds such as ragweed, sagebrush, pigweed, Russian thistle and cocklebur.
Pollens can travel as far as 400 miles and up to two miles high in the air
SOURCE: American Academy of Allergy, Asthma and Immunology
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CNN's Dr. Steve Salvatore looks at some of the treatments available for allergies.