Allergy testing: When to do it and what you can learn

It can start with a sneeze. Or maybe a rash after snack time. For many parents, signs of a potential allergy in their child can be worrying and confusing.

Allergies are common in kids, and so are questions. That’s why allergy testing can be a helpful first step in figuring out what’s really going on.

“Allergies happen when the immune system mistakes an otherwise harmless substance as a threat,” says Dr. Michael Lopez, an allergist and immunologist with Sharp Rees-Stealy Medical Group. “In people with allergies, the body treats things like peanut butter, pollen or bee venom as if they’re dangerous invaders.”

When that happens, the immune system can overreact, releasing chemicals like histamine that cause symptoms such as itching, swelling, sneezing or more serious reactions. And while not every child with a runny nose needs to be tested, some do, especially if symptoms are persistent or severe.

When to consider allergy testing

It may be time to talk to your child’s doctor if they’re regularly experiencing:

• Unexplained rashes or hives

• Chronic nasal congestion or sneezing

• Asthma flare-ups after exposure to pets or pollen

• Digestive issues after eating certain foods

“Sometimes symptoms alone don’t give us the full picture,” Dr. Lopez explains. “Testing helps us figure out exactly what a child is allergic to. That way, we can avoid guessing and avoid unnecessary restrictions or treatments.”

How allergy testing works

There are two main types of allergy tests: skin tests and blood tests. Your child’s doctor can recommend the best option based on their age, medical history and comfort level.

“Skin testing is often done right in the office and gives quick results,” says Dr. Lopez. “We place a small drop of an allergen on the skin and gently prick the surface. If the child is allergic, a small bump may appear, similar to a mosquito bite.”

Blood tests are another option, especially for younger children who have trouble sitting still or those who may be anxious about the skin test.

It’s important to remember that a positive test result doesn’t always mean a child is truly allergic. “We look at the size of the reaction and the child’s full medical history,” says Dr. Lopez. “The test result is just one part of the puzzle.”

What happens after a diagnosis

If testing confirms an allergy, the care team will work with you to develop a personalized treatment plan. This may include:

• Avoiding the allergen whenever possible

• Using medications to manage symptoms

• Considering allergy shots or other therapies for long-term relief

Just as important, your child’s care team will provide education and support, including how to respond to allergic reactions. “The goal is to keep the child safe and help them live as normal and comfortable a life as possible,” says Dr. Lopez.

Understanding what’s behind your child’s symptoms can bring peace of mind and a plan for moving forward. If you have questions or concerns about your child’s symptoms, talk with their doctor.

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