Allergic Reaction Causes
Many substances can trigger an allergic reaction.
The body's immune system has a patrol of white blood cells, which produce antibodies.
This antibody promotes production and release of chemicals and hormones called "mediators."
Histamine is one well-known mediator.
Mediators have effects on local tissue and organs in addition to activating more white blood cell defenders. It is these effects that cause the symptoms of the reaction.
- If the release of the mediators is sudden or extensive, the allergic reaction may also be sudden and severe.
- Your allergic reactions are unique to you. For example, your body may have learned to be allergic to poison ivy from repeated exposure.
- Most people are aware of their particular allergy triggers and reactions.
Certain foods, medications, latex, aspirin, shellfish, dust, pollen, mold, animal dander, and poison ivy are famous allergens.
- Bee stings, fire ant stings, penicillin, and peanuts are known for causing dramatic reactions in some people that can be serious and involve the whole body.
- Minor injuries, hot or cold temperatures, exercise, or even emotions may be triggers.
- Often, the specific allergen cannot be identified unless you have had a similar reaction in the past.
- Allergies and the tendency to have allergic reactions run in some families. You may have allergies even if they do not run in your family.
- Many people who have one trigger tend to have other triggers as well.
People with certain medical conditions are more likely to have allergic reactions.
September 02, 2005
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