Allergies Seasonal Pollen Triggers

Seasonal allergies occur after exposure to airborne substances that are only present at certain times of the year. An allergic reaction takes place when the body mistakes harmless substances for dangerous foreign invaders. The body’s immune system rallies to attack the “invaders,” causing chemical reactions in the body that produce histamine. The presence of histamine causes congestion, itching, sneezing and a host of other unpleasant allergy symptoms.

Understanding and Diagnosing Your Pollen Allergy

Pollen allergies are one of the most common types of seasonal allergy. Some people are allergic to only one kind of pollen, while others are allergic to many pollen types. Pollens are tiny, light grains that are released by flowering plants to help them reproduce. They are either be carried by insects or on the wind to cross-pollinate other plants of the same type.

Pollens transported by insects seldom cause allergies. Pollens carried by the wind, however, are a leading cause of seasonal allergies. As pollens travel on the wind, they are easily inhaled or can land on the eyes, nose or skin, triggering allergy symptoms.

The pollen cycles of various plants create seasonal pollen triggers during different times of the year. While certain types of plants typically pollinate during specific seasons, climate variations affect pollination schedules. Pollen levels are often the highest between 5:00 a.m. and 10:00 a.m., when many plants release their pollen into the air.

Autumn Pollen Allergies

If you suffer allergy symptoms in the late summer and fall, you may be allergic to weed pollen. Weeds usually pollinate during the fall months, and are the most common cause of autumn allergies. Here are some of the weeds that trigger fall allergies:

  • cocklebur
  • pigweed
  • ragweed
  • sagebrush
  • tumbleweed (Russian thistle).

In some parts of the world, trees also pollinate during the fall.

Spring Pollen Allergies

Most spring allergies come from tree pollen, although in some climates, weeds also may begin to pollinate in the spring. Depending on where in the world you live, trees can begin to pollinate any time between January and April. Trees that can cause severe springtime allergies include:

  • ash
  • birch
  • cypress
  • elm
  • hickory
  • maple
  • oak
  • olive
  • poplar
  • walnut.

Summer Pollen Allergies

The main cause of summer pollen allergies is grass. Grass pollen is highest during the summer; however, grass can cause allergies at other times of the year for allergic individuals, particularly if they mow the lawn or lie down in the grass.

There are two major categories of grasses. Northern grasses thrive in colder climates, while southern grasses are more commonly found in warmer areas. Some northern grasses that cause allergies are:

  • blue
  • orchard
  • red top
  • sweet vernal
  • timothy.

Bermuda is the main grass that causes allergies in the south.

Measuring Pollen Count

The amount of pollen in the air varies from day to day, and higher pollen counts are more likely to trigger seasonal allergy symptoms. To help people with allergies avoid pollen exposure, scientists measure the amount of pollen in the air each day during allergy seasons.

Pollen counts are usually taken with the help of silicone grease-coated clear rods. These rods are exposed to the air on a set schedule, generally over a 24 hour period. The samples are then stained and examined under a microscope to see how many grains of pollen have collected on a portion of the rod, or the entire rod. The pollen totals are converted to a concentration, generally in units per cubic meter of air.

Relieving Seasonal Allergies

Avoiding pollen exposure goes a long way toward helping you feel better during allergy seasons. Here are a few suggestions to help you minimize your exposure to pollen:

  • Keep doors and windows closed, caulked and sealed.
  • Stay indoors as much as possible during peak allergy seasons.
  • Use a high performance, allergy-free filter in your air-conditioning and heating systems.
  • Wash your hair, face and all exposed skin after spending time outdoors, and wash clothing in detergent designed to remove allergens.
  • Wear a pollen mask and gloves when working outside, particularly if you are mowing your lawn or cutting back trees or weeds.
  • When using the air conditioning in your home or car, choose the setting for re-circulated air.

When pollen avoidance isn’t enough, you can try one of the many over-the-counter allergy remedies, or visit your doctor for a prescription if you need stronger relief. Some common allergy treatments include:

  • antihistamines
  • decongestants
  • corticosteroid nasal sprays
  • cromolyn
  • eye drops
  • immunotherapy (allergy shots)
  • leukotriene modifiers
  • nasal irrigation with saline solution.

Resources

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