How long for an acth blood test to come back?

ACTH test time: It takes about 8 hours for our local university to run the ACTH test. Your results should be available the next day.

About 2 days: Many labs will differ how they run tests or advise how they be collected. For one lab an ACTH needs to be collected between 7-10 am and the turnaround is about 2 days. The ordering provider may not get the result exactly at 2 days if it has to be placed in the record or if it has to be signed off to be officially read however.