

-John Trever, Albuquerque Journal

California NORML's Drug Testing Tips -

Dealing With Urinalysis on Short Notice

Updated February 2011

While NORML strongly opposes drug use on the job, we think no one should be forced to submit to urine testing, especially for marijuana. Aside from launching a legal challenge, your best defense against urine testing is to be clean. Unfortunately, this may be difficult since urine tests may detect marijuana 1-7 days after an occasional use, 1-3 weeks in regular users, and up to 3 months in multiple daily users (more info). Since urine tests do not detect the psychoactive ingredient of marijuana, THC, but rather other, nonactive metabolites, they in no way measure impairment; nonetheless, this fact is of no account to employers in today's anti-drug hysteria. If you are on the job market, it is prudent to expect being tested and avoid marijuana. However, recognizing that many of you may face drug testing on short notice, we offer the following advice for emergencies with our best wishes (but no promises!).

We are sorry having to mention these devious techniques, but feel it is necessary to defend innocent people against wrongful accusations of drug abuse. We urge you to use this information responsibly and not as a way of hiding irresponsible marijuana use.

DON'T RELY ON EXCUSES

Although urine tests are far from infallible, it is difficult to challenge positive test results. "False positives," in which workers are wrongfully accused of drug use, are highly unlikely so long as labs exercise proper care (however, not all labs do this).

The Dept. of Health and Human Services has issued extensive mandatory guidelines for federal workplace drug testing programs (SAMHSA guidelines). They include safeguards to assure sample security, chain of custody, backup testing, and prevention of dilution and tampering. However, private employers do not regularly follow the SAMHSA guidelines, and even those required to do so are often derelict in following them diligently.



An essential safeguard in the SAMHSA guidelines is to to confirm all positive test results with a backup test. Samples are first screened with a so-called immunoassay test (e.g., EMIT or RIA). Positive samples must then be re-tested with the more accurate gas chromatograph mass spectrometer (GCMS). This virtually eliminates the chance of false positives in exchange for a relatively high rate of "false negatives," where drug use is not detected. The sensitivity of the test is determined by the concentration of metabolites it is set to detect: for the DOT and other federal testing programs, the standard cutoff is 50 nanograms/milliliter (ng/ml) of marijuana metabolite (THC-COOH).



No commonly used substance is known to produce a false positive for marijuana. One exception is a prescription drug for ulcers known as Protonix®, which has been reported to cause a false positive for THC on immunoassay tests. Other prescription and over-the-counter medicines can cause false positives for amphetamine and other illicit drugs on immunoassay tests. However, all of these legal drugs can be distinguished from illegal ones using a backup GCMS test. It used to be that certain hemp foods could cause a positive for marijuana, but this problem has been fixed.

If you are taking a drug that might confuse a drug test, you are supposed to report it beforehand. SAMHSA guidelines require that positive drug tests be reviewed by a medical review officer (MRO), who will excuse legally prescribed drugs.



"Passive smoking" of marijuana is not an acceptable excuse at the 50 ng/ml level, since only in extreme circumstances can a non-smoker absorb enough pot to test urine positive (e.g., being stuck in a closet full of heavy smokers for hours). However, heavy passive exposure may result in positive tests at 25 ng/ml or lower. We do know of people who have flunked a drug test after accidentally ingesting a tainted brownie; unfortunately, this excuse didn't impress their employers.

MEDICAL MARIJUANA

Although a growing number of states allow medical use of marijuana, they do not generally protect patients from drug testing. While some employers in medical marijuana states allow for medical marijuana, most do not, and those under federal regulations are specifically forbidden to do so. If marijuana were treated consistently with other drugs such as prescription amphetamines and opiates, medical users would be excused from positive drug tests if they had a doctor's prescription. State law in this area is evolving. While the California Supreme Court has ruled that the state's medical marijuana law does not protect patients from drug testing (Ross v. RagingWire), an Oregon appeals court has held otherwise. Further legal challenges seem likely as medical marijuana becomes more accepted.



One possible excuse for a positive marijuana test that sometimes works is a prescription for Marinol®, the FDA-approved synthetic marijuana pill that is currently available as a schedule 3 prescription drug. Marinol used to be indistinguishable from marijuana on both immunoassay and GCMS tests, creating a valid medical excuse for a false THC positive. However, some labs have begun to adopt a new technology that can distinguish Marinol from marijuana. Obnoxious as it may be for employers to fault employees for using marijuana instead of Marinol, use of Marinol can no longer be recommended as a technique for evading unfair drug tests.

WASH YOURSELF OUT

The general strategy for passing urine tests is to increase your fluid intake and urine flow so as to dilute the concentration of drugs in the sample below the threshold of detection. An hour or two before the test, you should fill your bladder with a quart or two of water. Water is fine - contrary to popular rumor, there is NO evidence that goldenseal, vinegar, niacin, or vitamin C help. Many people wash themselves out for several days in advance by drinking a lot and exercising, but there is no reason to think this is useful. In no case should you give your first urine of the morning, since drug metabolites tend to build up during your sleep.

