The health care provider will place a special paper strip inside the lower eyelid of each eye, under the eyelid (usually the bottom one). Both eyes are tested at the same time. Before the test, you will be given numbing eye drops to prevent your eyes from tearing due to irritation from the paper strips.
The exact procedure may vary. Most often, the eyes are closed for 5 minutes. Close your eyes gently. Closing the eyes tightly or rubbing the eyes during the test can cause abnormal test results.
After 5 minutes, the doctor removes the paper and measures how moist it is.
Sometimes the test is done without numbing drops to test for other types of tear problems.
The phenol red thread test is similar to the Schirmer's test, except that red strips of special thread are used instead of paper strips. Numbing drops are not needed. The test takes 15 seconds.