Drug Testing

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Urine Drug Testing

Companies use urine drug tests to screen applicants and ensure employees follow drug-free policies. Illegal drug use is associated with increased employer costs, including absenteeism, reduced productivity, and workplace accidents. Screening applicants and employees helps employers reduce these incidents.

Government-mandated testing

Urinalysis is also the only testing option approved for federally-mandated drug tests. Parolees may be subject to periodic urine tests as a condition of their parole. Government workers must also pass a drug screen and may be subject to random drug testing. Industries under the regulation of the US Department of Transportation must comply with state and federal drug testing standards as well.

Athletic urine testing

Athletes, particularly those in professional associations, may be subject to random drug tests. Olympic hopefuls must pass repeated drug screens for steroids and other performance-enhancing drugs. Many high school and college athletic teams also require random drug testing.

Urine test screening

Urine drug testing screens for a variety of substances, including but not limited to

  • Amphetamine or methamphetamine
  • Cocaine
  • Opiates, such as oxycodone or heroin
  • Marijuana and synthetic cannabis such as K2 or Spice
  • Benzodiazepines like Valium or Xanax
  • Ecstasy and methadone
  • Alcohol
  • Phencyclidine (PCP)
  • Synthetic stimulants such as Bath Salts

Reviewing urine drug test facts

Urine drug tests target drug use within the past 24-72 hours. However, the actual detection window depends on the type of drug and frequency of use. For example, heavy marijuana users may produce a positive result up to a month after quitting.

False positives

Certain medications and foods can cause false positives on a drug urinalysis. For example, ingesting poppy seeds or dextromethorphan, a cough suppressant, can cause a false positive for opiates. Ephedrine, a decongestant, can cause a positive result for amphetamines. Prescription diet pills may also register as amphetamine or methamphetamine. Some prescription painkillers and cough suppressants contain codeine. The body changes codeine into morphine so that both substances may appear on the drug test.

However, false positives for other substances are practically impossible. For instance, there is no prescription for PCP or cocaine. Doctors may rarely use heroin or cocaine in a medical setting, but any legitimate use of these substances will be well documented.

Companies that analyze drug test results

There are only a few companies that provide urine drug test analysis. They include

  • Laboratory Corporation of America Holdings
  • Lenexa
  • National Toxicology Labs, Incorporated
  • Pharmatech, Incorporated
  • Quest Diagnostics, Incorporated

The federal government may use other companies for workplace testing through the Substance Abuse and Mental Health Services Administration (SAMHSA)

Identifying types of urine testing for drugs

Most companies use a 5-panel or 10-panel drug test. The panel number corresponds to the number of substances the test covers. The 5-panel test covers amphetamines (including methamphetamine), cocaine, marijuana, PCP, and opiates like codeine and morphine. In addition to these substances, the 10-panel test also screens for alcohol, barbiturates, benzodiazepines, methadone, and propoxyphene, a narcotic painkiller.

12-panel urine drug test

Some testing facilities offer a 12-panel drug test. This test extends the 10-panel test to include commonly abused prescription drugs and Ecstasy. Certain testing companies may offer the option of screening for designer drugs as well.

Using the right test

Members of law enforcement, civil servants, and medical personnel must pass a 10-panel drug test. A 10-panel test is also common when testing individuals who are on probation or parole for criminal offenses.

Companies may choose to extend or reduce the scope of a 5-panel test. For example, in states where marijuana use is legal, some businesses may not test for THC, the active compound in cannabis. In factories, machine operators and forklift drivers may have to pass a 7-panel test. The additional screening covers prescription medications that could impair the employee’s ability to operate industrial equipment safely.

However, the exact test used depends on state and federal guidelines. For instance, marijuana is legal in the state of Colorado, but it is still a federal offense to use the drug. The proprietor of a bike shop may not care whether their employees use the drug, but someone working in a federal facility cannot have it in their system.

Recognizing urine drug test detection times

Several factors influence how long a drug is detectable in urine. They include the person’s fluid intake and hydration levels, how fast their body metabolizes the drug, and frequency of use. Other determining factors are how the drug entered the body and the concentration cutoff levels the testing laboratory uses.

Test ranges

The following detection times are general guidelines that vary according to the factors listed above.

  • Alcohol – 2-12 hours
  • Amphetamines, including methamphetamine – up to two days
  • Barbiturates – two days for short-acting barbiturates, 1-3 weeks for long-acting barbiturates
  • Benzodiazepines – three days for a therapeutic dose, 4-6 weeks for chronic use
  • Cocaine – 1-4 days
  • Codeine – two days
  • Ecstasy – up to two days
  • Heroin – two days
  • Ketamine – 5-7 days
  • Marijuana – 2-7 days for single use, 1-2 months or more for extended, chronic use
  • Methadone – three days
  • Morphine – two days
  • Opiates – 5-7 days
  • PCP – 8-14 days for occasional use, up to 30 days with chronic use
  • Propoxyphene – anywhere from six hours to two days
  • Steroids – 14-28 days taken orally, 1-3 months if injected

Answering frequently asked questions (FAQs) about urine drug testing

Many people wonder whether secondhand exposure to marijuana smoke will show up on a drug test, what to do when a test shows a false positive, and whether it is possible for a test to give a false negative. Here are the answers to those questions.

Secondhand exposure to marijuana

Laboratory testing has set cutoff values for each substance. Generally speaking, the amount of THC exposure a person receives from being in the same room with marijuana smokers is well below that cutoff level.

Dealing with false positives

If your results produce a false positive, you still have some options. First, make sure you provide a list of recently used prescription and over-the-counter medications. Having medical documentation for certain substances may provide an adequate explanation of the drug’s presence in your system. However, this depends on the reason for the test and the agency ordering it. For example, an unsafe level of benzodiazepines in your system can impair an equipment operator’s ability to react, regardless of whether they have a prescription.

Second, you can request a more accurate retest of the same sample, usually at your expense. This second test is called gas chromatography/mass spectrometry (GC/MS). This test is more expensive, but it rarely produces a false positive. However, the cutoff point for detecting some drugs is lower with GC/MS. For example, you must have at least 1,000 parts per milliliter to test positive for amphetamines on a standard urine drug test. A GC/MS of the same sample only requires 500 parts per milliliter to produce the same result.

Producing false negatives

No test is 100 percent accurate, so it is possible for a test to produce a false negative. However, law enforcement agencies and other organizations with strict guidelines may use hair, saliva, or blood tests to verify results.

Deliberately altering urine specimens to pass a drug test is not recommended. Only a handful of companies analyzes urine drug tests. Samples must often pass a quality analysis that includes measuring pH, temperature, and the concentration of certain waste products in the body. The quality control tests can detect additives and diluted samples, both from excessive water consumption or from tap or toilet water added to the specimen.

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