Will vicodin show up in a drug test?

Generally, yes.

It depends on the test given, and how recent the Vicodin (containing hydrocodone) was taken.

But in general, yes. Most drug tests will test for Vicodin (hydrocodone and/or its metabolities). Hydrocodone metabolizes into hydromorphone--another opioid (brand name: Dilaudid).

In that case, it would test positive for opioids/opiates.

If you have a prescription, then there is no problem legally.