Veritatum17 replied: "Looking at the drug combination you're taking, I'm not surprised that your test came back positive. Let me explain: Consider that cocaine is an serotonin reuptake inhibitor (SSRI) and dopamine reuptake inhibitor (DARI) like Wellbutrin; its also a norepinephrine reuptake inhibitor (NARI) like Lexapro, and an opioid like Lortab. In other words, the urine test is looking for evidence of generic compounds that act upon specific parts of the brain; while it is common to find one interaction, you've got four. That's what makes it really difficult to say "yeah, that positive is false. I'm taking four meds that cover it." The medical testing companies generally hire techs to look over the results, and these techs are more concerned with following procedure than with advanced knowledge of pharmacology - and that's what they need to be. But it doesn't help people who take multiple drugs with multiple psychotropic impacts. The major difference between the medical cocktail you're taking and cocaine is that none of these medications are known to act on the mesolimbic reward pathway, which is where cocaine is addictive. It's also where dopamine and serotonin are commonly found, both of which are naturally occuring, so its not the sort of thing one can test for and say "ah! there's drug use!" One thought is to offer to pay for your own test by another company, and call around to companies, tell them what medications you're on, and ask if these can be screened out. If not, you'll want to talk with your doctor about altering your medication. I'm not a medical professional, but I'd honestly ask your doctor or doctors to alter your treatment if at all possible anyway. You have four very powerful psychoactive medications going through your body, I have to wonder if there's some way to taper down to one or two. I mean, Lexapro is recommended where SSRIs aren't effective - maybe your doctor will consider tapering you down from Wellbutrin? Don't adjust your doses without talking with your doctor first, though. I had a buddy who did and he ended up catatonic for two days. The antibiotic should have no impact, though to avoid interactions, make sure you fill all your scripts at the same pharmacy, or at least notify each pharmacy you use of each medication you use. Lastly, it won't do much good to simply present a doctor's note (even hard research out of JAMA) that says that your combination of drugs can cause a false positive. A company isn't going to scrap its drug testing program because a combination of fairly routine drugs will give false positives. They will scrap it if there are false negatives, mind you, but to be more safe means that there are fewer legal risks, and that's the entire bloody point of drug testing. Good luck in your job search."