They will take blood from your arm. Doesn't take long at all. I have to get blood draws all the time for my thyroid tests and it takes less than 5 minutes.
They then send your blood out to a lab who tests it for whatever the doctor wants to know. In about 3 days they send the information to your doctors office. Your doctor will read the results and either call you with them or mail them to you, again it depends on the test you are getting.
Sometimes, especially if you will be put on a medication, they have you come in for another office visit. If they do that you just go in and the doctor will talk to you about what your test results mean and probably give you a prescription to help the problem.
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