Will Vyvanse and phentermine show up the same on a drug test?

I am assuming that you mean "phenteramine."

The answer is YES, both show up in drug screens. Drug screens do not test for specific drugs, only broad classes of drugs like amphetamines and benzodiazepines. Phenteramine, being a sympathetic amine of amphetamine (an "amphetamine congener") will make a drug test show up as "hot" for amphetamine. Same thing with Adderall, which is simply four different salts of amphetamine mixed together.

Hope this helps,

Dr. Ron