hair test

Hair holds a lot of information. I have never heard of an employers going as far as hair testing. It is extremely expensive. If you are prescribed Percocet, have a copy of your prescription AND a note from your doctor IF it should come up. Don't volunteer information.
I volunteered that I have been treated for leukemia to one prospective employer and now no one wants to hire me....so be careful what you say.

In all likelihood the answer is no. Vicodin (Hydrocodone Bitartrate and Acetaminophen) can be distinguished from Percocet (Oxycodone and Acetaminophen) but that is an advanced test that should not be used in pre-employment testing.

One (1) Vicodin taken 60 days previous should not show up at all even if specifically tested for. In fact, unless you are on high dosage of Percocet, it is also unlikely to show up.

Unless you have been offered the job, the prospective employer should be testing only for illegal drugs....not prescription. If that is the case then neither will be detected.

Handyman2007 offered excellent advice. Don't volunteer information about medical conditions or prescriptions, unless you have been officially offered the position....and the prospective employer cannot legally inquire. In employment drug testing there is a clear line drawn between a drug test and a medical examination.

The purpose of this distinction is to prevent the employer from denying employment based on disclosure of a disability.

Ref.
ENFORCEMENT GUIDANCE: DISABILITY-RELATED INQUIRIES AND MEDICAL EXAMINATIONS OF EMPLOYEES UNDER THE AMERICANS WITH DISABILITIES ACT (ADA)