The sweat test is a simple, painless diagnostic test used to measure the salt content of sweat to determine whether someone has cystic fibrosis.
No special preparation is needed prior to the test, other than to avoid treating the test area with any creams or lotions for 24 hours before the test, which takes about an hour. No injections are used in this procedure.
A small area of skin on the arm is washed and dried. Two electrodes are attached to the arm with straps. One of these electrodes has a disk containing pilocarpine gel, which increases the production of sweat.