How long does amphetamines and hydrocodone stay in your system before you can pass a urine test? Anything I can do to assist with getting it out?

For urine drug testing (UDT) purposes you chose an unfortunate combination. Hydrocodone is seldom detected in standard (5-panel) UDTs. Amphetamines, on the other hand, are routinely detected via the same tests.

Detection time for amphetamine? Anywhere from 1-5 days. In other words individually meaningless.

Detection time for hydrocodone? Comparable to amphetamine, but far less likely to be detected.

Means for increasing rate of elimination? I have never researched the many claims in relation to the various drugs. Keep in mind that each drug works in a specific way within your body, so a singular agent is unlikely to counteract both.