Allergic rhinitis a.k.a hay fever
"Hay fever" is a misnomer. Hay is not a usual cause of this problem and it does not cause fever. Early descriptions of sneezing, nasal congestion, and eye irritation while harvesting field hay promoted this popular term. "Allergic rhinitis" is the correct term used to describe this allergic reaction. Rhinitis means "irritation of the nose" and is a derivative of "Rhino," meaning nose.
Symptoms of allergic rhinitis frequently include nasal congestion, a clear runny nose, sneezing, nose and eye itching, and tearing eyes. Observers of the person experiencing allergic rhinitis will commonly notice frequent rubbing of the nose using the index finger. This is the so called "allergic salute."
An allergic reaction occurs when the immune system attacks a usually harmless substance called an "allergen" that gains access to the body. The immune system calls upon a protective substance called "immunoglobulin E" or "IgE" antibodies (for erythema or redness) to fight these invading allergic substances or allergens. Even though everyone has some IgE, an allergic person has an unusually large army of these IgE defenders. This army of IgE antibodies attacks and engages the invading army of allergic substances of allergens.
As is often the case in war, innocent bystanders are affected by this battle. These innocent bystanders are special cells called "Mast" cells. These cells are frequently injured during the warring of the IgE antibodies and the allergic substances. When a mast cell is injured, it releases a variety of strong chemicals into the tissues and blood. One of the chemicals released by the mast cells is histamine. These chemicals are very irritating and cause itching, swelling, and fluid leaking from cells.
Many trees, grasses, and weeds produce extremely small, light, dry protein particles called pollen. These pollen particles are usually the male sex cells of the plant and are smaller than the tip of a pin or less than 40 microns in diameter. Pollen lodges in the nasal lining tissues (mucus membranes) and other parts of the respiratory tract where it does harm to an allergic person. A person is programmed to be allergic by his/her genetic makeup and is destined to be allergic from birth.
Antihistamines combat the histamine that has been released during an allergic reaction by blocking the action of the histamine on the tissue. Antihistamines do not stop the formation of histamine nor do they stop the conflict between the IgE and antigen. Therefore, antihistamines do not stop the allergy "war" but protect tissues from the fallout of the "war."
Symptoms of allergic rhinitis frequently include nasal congestion, a clear runny nose, sneezing, nose and eye itching, and tearing eyes. Observers of the person experiencing allergic rhinitis will commonly notice frequent rubbing of the nose using the index finger. This is the so called "allergic salute."
An allergic reaction occurs when the immune system attacks a usually harmless substance called an "allergen" that gains access to the body. The immune system calls upon a protective substance called "immunoglobulin E" or "IgE" antibodies (for erythema or redness) to fight these invading allergic substances or allergens. Even though everyone has some IgE, an allergic person has an unusually large army of these IgE defenders. This army of IgE antibodies attacks and engages the invading army of allergic substances of allergens.
As is often the case in war, innocent bystanders are affected by this battle. These innocent bystanders are special cells called "Mast" cells. These cells are frequently injured during the warring of the IgE antibodies and the allergic substances. When a mast cell is injured, it releases a variety of strong chemicals into the tissues and blood. One of the chemicals released by the mast cells is histamine. These chemicals are very irritating and cause itching, swelling, and fluid leaking from cells.
Many trees, grasses, and weeds produce extremely small, light, dry protein particles called pollen. These pollen particles are usually the male sex cells of the plant and are smaller than the tip of a pin or less than 40 microns in diameter. Pollen lodges in the nasal lining tissues (mucus membranes) and other parts of the respiratory tract where it does harm to an allergic person. A person is programmed to be allergic by his/her genetic makeup and is destined to be allergic from birth.
Antihistamines combat the histamine that has been released during an allergic reaction by blocking the action of the histamine on the tissue. Antihistamines do not stop the formation of histamine nor do they stop the conflict between the IgE and antigen. Therefore, antihistamines do not stop the allergy "war" but protect tissues from the fallout of the "war."
posted by Widi Voorwinden at 10:27 am
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