Preparing Your Child for a Sweat Test

Your healthcare provider may ask for a sweat sample to gather more information about how your child’s body is working. This appointment will take about an hour.

To prepare for your visit, please remember:

  • Creams and lotions should not be applied to the skin 24 hours before the procedure.
  • Drink plenty of fluids to be well hydrated.
  • Arrive early for your appointment time to allow for check-in.
  • Allow 45 minutes to an hour to complete the test.
  • Please bring your insurance information at the time of your visit.
  • Please ask your healthcare provider for the results of your test.

What to Expect During a Sweat Test
Illustration of a child undergoing a sweat test

  1. First, the arm is cleaned with alcohol and water.
  2. Next, two gel disks and electrodes are secured to the skin. Both are wrapped with a large latex-free band.
  3. The electrodes are connected to a machine for 5 minutes. This may cause a tingling sensation. This may be irritating but is not painful.
  4. The electrodes are removed and a collection device is secured to the skin. You will need to keep it wrapped for 30 minutes.
  5. The sweat is collected after 30 minutes and the collection device is removed.
  6. This process will take place on two limbs.


  • There may be redness around the skin where the electrodes were placed but skin will return to normal color within an hour or two.
  • The electrodes are not harmful although they may cause a tingling/annoying feeling.


To schedule a sweat test appointment, please call 312.227.6350.


Sweat tests are conducted in the Outpatient Lab of the main hospital. Our hours Monday through Friday are 8-10 a.m.