Skin Prick Test: what to expect

In shortA skin prick test places tiny allergen drops on the skin to see which ones cause a small raised bump. It takes about 30 minutes and feels like a light scratch.

When I say "allergy test", many parents picture needles and tears. The good news is that the skin prick test is one of the gentlest tests we do. Most children are far more curious than upset, especially when we let them watch.

What is a skin prick test?

We place tiny drops of common allergens on the skin, usually the forearm or back. These can include dust mites, pollen, moulds, pet dander and certain foods. The skin under each drop is then lightly pricked so that a very small amount reaches the surface. If your child is allergic to one of them, a small itchy bump appears in a few minutes, much like a mosquito bite.

Who might need one?

I suggest the test when a child has symptoms that keep coming back and the cause is not clear, for example:

• Repeated sneezing, itchy eyes or a blocked nose
• Cough or wheeze that returns again and again
• Eczema or rashes that flare up for no clear reason
• A suspected reaction to a particular food

It is not a routine test for every child. The doctor decides after listening to the story and examining your child.

Before the day

This is the part that matters most. Many allergy and cold medicines, including some common syrups, can hide the reaction and make the test unreliable. We will tell you which ones to stop and for how many days. Please do not stop an asthma inhaler or any other prescribed medicine unless we have asked you to.

What happens on the day

The whole visit takes around 30 minutes, and most of it is waiting for the skin to react. Bring a book, a toy or a tablet. The key rule for little ones: no scratching! It is hard, I know, and a distraction really helps.

How we read the results

We compare each bump with a reference, and measure it. A larger, raised bump with a red edge is a positive reaction. No reaction is a negative result.

A positive result does not automatically mean that the allergen is the cause of your child's symptoms. A skin test shows what the body is sensitive to. We always read it together with your child's history before making a plan.

And then?

The result guides practical steps: avoiding or reducing triggers, the right medicines, and, for some children, long-term treatment such as immunotherapy (allergy drops under the tongue), which we offer at the clinic. You can read more on our allergy and asthma page.

Is it safe?

Yes. The test is done in the clinic, where trained staff can look after your child straight away. Serious reactions are uncommon, and your child will be watched throughout.

Dr. Mahima Shetty KR
Consultant Pediatrician, MBBS, MD (Pediatrics). Sees patients Mon–Sat at CARE Speciality Clinic, HSR Layout.

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This article is for general information and does not replace a medical consultation.