Allergic reactions are reactions to a substance that can be caused by a single ingredient, such as an ingredient in a product.
However, there are many other possible triggers and symptoms, and these can be allergen triggers.
A more common cause of allergic reactions is contact dermatitis.
Contact dermatitis is when a person has a reaction to contact with an allergenic substance such as a chemical, such a glue, or a piece of clothing.
The reaction may be mild or severe, and is not caused by any other substance.
For example, someone who is allergic to glue may have a mild reaction to glue, but may have another reaction if they use the glue in their daily activities.
Contact with an anaphylactic chemical, for example, may cause contact dermatosis or allergic contact dermatoses.
In addition to allergens, there is also contact with other potentially allerging substances, such that people who are allergic to latex may have contact with latex-containing products, and people who have allergic reactions to certain medications may be at increased risk of developing a potentially allergens-related reaction.
For more information, check out this article from Health.com.
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