The Leeds Teaching Hospitals NHS Trust

Skin Prick Testing

 One way we can diagnose allergies is through skin prick testing. This is a safe and simple way to determine what your child is allergic to. You will know the results of these tests on the day of your clinic. The way this is done is by placing a small drop of the allergen onto your child's forearm, and lightly pricking it into the skin. Multiple allergens can be tested at once.

Step-by-step process:

Here is listed the steps of skin prick testing, from start to finish. You may wish to explain this to your child prior to their appointment, to help them to prepare.

1. Your child will need to sit on a chair close to the nurse, either by themselves, or on your knee.

2. The nurse will take one of your child's forearms, and write some letters on their forearm. Each letter will correspond to the allergen being tested.

3.The nurse will then place a drop of solution next to each letter; each solution contains a different allergen.

4. The nurse will then lightly touch through each drop, with a very small metal lancet. The sensation your child will feel is similar to a small scratch.

5. The nurse will then use a tissue to blot the solutions off the skin, and send you to the waiting area for 10-15 minutes - this is the time it takes for the skin reactions to occur,

6. The nurse will then measure and record the size of each allergen, which will help to determine a plan for your child.

About the solutions we use:

  • The solutions we use in skin prick testing contain a diluted and safe amount of the allergen. Skin prick testing is very safe and is highly unlikely to cause an allergic reaction. Most children will develop a small hive (nettle sting rash) to an allergen they are allergic to. This resolves in 20-30 minutes, however allergy medication is readily at hand if needed.
  • Although we can test for a wide variety of food and environmental allergens, we obtain more accurate results from fresh fruit and vegetables rather than the solutions. For this reason if you would like your child to be tested to these, we suggest bringing a small piece of the fresh fruit or vegetable (not tinned or cooked).
  •  Skin prick tests are not particularly painful. Most children describe it as a 'scratch' or a 'pin prick'. We are very experienced in doing skin prick testing gently and patiently on anxious and frightened children.
  • We have a wide variety of solutions for skin prick test, ranging from foods, to pollens, dust mites and certain moulds.
  •  In rare occasions, we may arrange to bring your child back on a second appointment for further skin prick testing.
  •  There are some foods which we do not have skin prick test solutions for, please feel free to contact us prior to your child's appointment if you have any questions regarding this.
  •  It is important your child has not taken any antihistamines prior to their clinic appointment. Antihistamines can alter the results of a skin prick test, and could lead to incorrect results. Of course, we understand that this may be difficult for some children, and would not recommend avoiding their antihistamines if they really need it. If they have needed a dose within the 5 days prior to the appointment, we would recommend still attending the appointment. You can also ring the children's allergy nurses if you have any queries about this.

 Before your clinic appointment:

  • We have a wide variety of solutions for skin prick test, ranging from foods, to pollens, dust mites and certain moulds.
  •  In rare occasions, we may arrange to bring your child back on a second appointment for further skin prick testing.
  •  There are some foods which we do not have skin prick test solutions for, please feel free to contact us prior to your child's appointment if you have any questions regarding this.
  •  It is important your child has not taken any antihistamines prior to their clinic appointment. Antihistamines can alter the results of a skin prick test, and could lead to incorrect results. Of course, we understand that this may be difficult for some children, and would not recommend avoiding their antihistamines if they really need it. If they have needed a dose within the 5 days prior to the appointment, we would recommend still attending the appointment.