It does cause you to fail a drug screen. It shows up as an amphetamine. My dr said it is considered a false-positive. If you have a prescribing dr for the adipex they will typically give you a letter to give to your employer, or whomever may be ordering the drug test. Doctors give trusted answers on uses, effects, side-effects, and cautions: Dr. Smith on how long does phentermine stay in your system: This medication is generally dosed once to twice daily. Clinical effect generally gone in twenty four hours. Blood levels generally depleted in five half lives believe 60 hours. Doctors give trusted answers on uses, effects, side-effects, and cautions: Dr. Russell-Jenkins on adipex drug test: Although Provigil is a stimulant of sorts, its chemical makeup is dissimilar to amphetamines and should not cause a false positive drug test. Just wondering how long Phentermine will show up in a blood drug test. I have a script for phentrizermine but a friend gave me a Phentermine and wanted me to try it instead of what I was taking , now … I take some pain med's but have gained over 100 pd's in the past couple of years and need some help to loose the weight. I take a Urine Drug Screen monthly and want to know how long the will be in my system before I take my drug screen. Will taking 1 adipex show up on a drug test as cocaine? I have a prescription for them but I let my boyfriend try one early Sunday morning and he found out he has a drug test (urine) Tuesday morning. Because Adipex is closely related to amphetamine stimulants, it can often show up as a positive amphetamine on a drug urine test. Typically amphetamines and related medications will show up as positive in the urine for up to two full days after ingesting them, so I think it is very likely that this medication will show up on your urine drug test tomorrow. If you have a medical prescription for. In addition to the numerous adverse physical effects extended or overuse of the drug can cause, because it affects the body’s nervous system in much the same way as amphetamines, Phentermine can be habit-forming. Read thoroughly if you want to know does Phentermine show up in a urine drug test. How long does Phentermine stay in the urine? This is one of the most asked questions about Phentermine because of its similarity to amphetamines and false-positive results of a drug screen. And the answer is — like for other drugs, time frames vary from person to person. The half-life is 16-31 hrs if a. How long does Oxycodone show up in a urine drug test? Oxycontin gets out of the system pretty quick, for the average person, 48-72 hours but more likely 72 hours unless your really small and frail.