how long to you wait to check a tb test
Go to your doctor for the tuberculosis skin test. You will be given an injection of a purified protein derivative into the inner forearm that will result in a 6-10 mm welt that will disappear within a few hours. 2. Leave your arm uncovered. Do not place a bandage over the site of the test for the required 48 to 72 hours. You can wash and dry your arm carefully. You also should not scratch or rub the test area on your arm. This can cause redness or swelling that may cause the results to be misread.