The answer may not be so clear because even the word allergy itself has us scratching our heads. It's thrown around a bunch, but, technically, an "allergy" is when you have a reaction that involves the production of IgE antibodies, which cause an inflammatory response in the body. Not pretty.
So, here are the basics: If the irritation goes away once you rub the stuff off your skin, it's simply an irritant. If the reaction lasts — or if you get a similar occurrence with products that have the same ingredients — it's likely allergic.
Still a little confused? Head over to The Telegraph to figure out your situation. The more you know... (The Telegraph)
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