Drug Tests: How to Avoid False Positives

If you need to take a drug test for employment, getting or keeping a job may depend on a negative reading (Read Drug Testing in the Workplace: What Are Your Rights?).  Athletes, too, should know what to expect before undergoing a drug test prior to a competition (Read Athletes with an Edge: How Far is Too Far?). Or, if you’re a parent who uses home kits to monitor your children, you shouldn't necessarily panic if a test strip changes to the “bad” color (Read Drug Testing in Your Home: Pros and Cons). Even if you (or your kids) aren’t taking illegal drugs, there are some substances that can still cause the test to come back positive, which can result in a few headaches at best and legal problems, a pink slip, disqualification from sporting events, or family misunderstandings at worst (Read Legal Problems? 10 Questions for a Criminal Attorney).

How long does it take for substances to leave my body?

The period a drug or other substance stays in your system varies for each individual and depends on the type of substance (Read Back to Sobriety: How Long Different Substances Stay in Your System and Response to Substances: Why it Varies by Person).

Other than the obvious (i.e., drugs or alcohol), what can cause a drug test to come back positive?

A study conducted by Smith et al. and presented at the annual meeting of the American Psychiatric Association (APA) indicated that a number of substances can cause false positives on drug tests.  These are listed below by the type of drug that you could test “positive” for:

Amphetamines: Wellbutrin (bupropion), cold medicines, tricyclic antidepressants

Benzodiazepine: Daypro (oxaprozin), Zoloft (sertraline)

Marijuana/THC: Sustiva (efavirenz), extremely concentrated second-hand marijuana smoke

Opiates: poppy seeds, rifampin, dextromethorphan, quinolones

Are any drugs less likely to be caught?

The Smith et al. study found that many “general drug tests” don’t specifically test for the metabolites of opioids like methadone, oxycodone, tramadol, fentanyl, and buprenorphine.  Likewise, in terms of benzos, Xanax, Ativan, and Klonopin may require a special test to be picked up.  However, these drugs can still be detected if the right test is ordered and so you should not assume that you can continue to take these drugs and pass a test.

What should I do if the test is positive but I know that I didn’t take any illegal drugs?

If a urine test results are positive, request a blood test, which will provide an actual amount instead of just indicating “positive” or “negative.”  If you haven’t ingested a drug, the reading should fall below the cut off.  If you were taking a prescription or over-the-counter medication for an illness, ask your doctor to write a letter to your employer or coach explaining the situation.

What can I do for someone who is in danger of failing a drug test because they have a substance abuse problem?

eDrugRehab has helped numerous people return to a healthy, sober life.  Call our toll-free number now to discuss intervention services or to find a rehab facility.

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