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Allergies Health Center

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Could It Be an Allergy?

Telling the difference between an allergic reaction and something else can be tricky.

How to Recognize an Allergy continued...

If nasal allergy symptoms get worse in the spring or fall when pollen counts are generally higher, then it's more likely to be an allergy. "However, if they happen all the time, then you still have to figure out if you have a year-round allergy, which is commonly due to indoor allergens like dust, pets, or cockroaches," Resnick says.

It's not just a gut feeling. "With food allergy, you're not just looking for gastrointestinal symptoms like stomach cramps, diarrhea, bloating, or upset stomach -- you're also looking for a rash, or respiratory symptoms – something that goes beyond the GI tract," Goldsobel says. The reason? Food allergies are usually a multiple system reaction. So if just one organ system appears to be involved, it's more likely to be something else, such as an intolerance, insensitivity or even food poisoning.

Rule out brain and nervous system disorders. According to the National Institute of Allergy and Infectious Diseases, certain disorders often thought to cause food allergies either do not have enough research to support a link, or they have been disproven to be related. Among them are migraine, hyperactivity in kids, and certain disorders related to brain and central nervous system functioning -- mainly characterized by symptoms of fatigue, nervousness, and trouble concentrating combined with headaches. So most likely, you can eliminate food allergies from the list of possible culprits for these symptoms.

"A lot of parents come in saying their child's behavior or mood or irritability is due to a food allergy, and they're basically wondering what food is going to make them turn into a well-behaved, calm child – that's really what's being asked," Goldsobel says. "Unbiased research studies show that in the absence of other symptoms, just effects on the brain in terms of thought processes, mood, or behavior are extremely uncommon as a manifestation of food allergy," he says.

When You Can't Figure It Out on Your Own

Sometimes it's nearly impossible to tell if you're having an allergy short of being examined by a doctor. The prime example: a skin allergy from contact with a substance.

"For the person who is having the symptoms, there is probably no defining difference between allergic contact dermatitis and irritant contact dermatitis – both are going to irritate the skin the same way," Goldsobel says. Unless you're tested, it's not really possible to tell if you're having an immune response or not. But in the end, the solution is usually the same – avoid contact with whatever is causing the irritation.

If allergy symptoms continue to bother you and at-home treatments (including avoidance of symptom triggers) fail to work, or if you're still unable to tell if you're having an allergy or something else, then it's time to talk to your primary physician or see an allergist for a full evaluation.

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Reviewed on March 04, 2010

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