Keystone Laboratories Inc.

Urine Toxicology Testing

Multiple Testing Specialties

Keystone Laboratories provides customizable solutions for providers with industry-leading specialists in urine, oral fluid and blood specimen testing.

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Keystone meets the standards from CLIA, FDA and OSHA. CAP requirements commonly exceed the standards, bolstering patient care and safety.


Years Of Trusted Laboratory Testing Experience

Urine Toxicology Testing

The Trusted Company For Urine Toxicology Testing

Providers need to be able to make treatment decisions with absolute confidence. In order to do that, you need a urine toxicology testing solution that is both timely and reliable. Keystone has been working with providers since 1987, and we’ve learned that most providers aren’t able to get the urine toxicology testing they need when they need it. That is why Keystone offers you a host of testing and monitoring services so that every treatment decision you make is a confident one.

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About Urine Toxicology Testing

A toxicology screen is a test that determines the amount and type of legal or illicit drugs you’ve consumed. It can be used to test for assessing drug intoxication, overdose issues, track a substance abuse problem, or due to general drug abuse. Toxicology screening can be completed fast. A urine or blood sample is usually used for the test. In some circumstances, a saliva or hair sample may be used. The results may indicate the presence of a single drug or a combination of medications. Additional testing may be required to identify the precise amount of a specific medicine in the body and to confirm the results.

Most toxicological tests provide only a limited amount of information regarding how much or how frequently a person has taken a substance. Toxicology screening findings are often positive or negative. A positive test result indicates the presence of a drug or drugs in the body. When your doctor detects the presence of a drug through screening, a more specific test may be performed to determine how much of the substance is present, which we will talk about a bit later.

A two-tiered approach is used for forensic drug testing in urine, an initial enzyme immunoassay (EIA) drug screen followed by mass spectrometry (MS) confirmation analysis. The drug screen provides a qualitative positive or negative result for several drugs or drug classes. A positive result presumptively indicates that one or more drug(s) in that drug class is present in the sample. A negative result would indicate that the drug screened or compounds in that drug class are not present in the sample or are present below the cut-off concentration. Positive screening results require further testing to conclusively determine the presence of the drug and to accurately quantify the concentration of the drug in urine. This testing is called confirmation testing and it uses both gas chromatography mass spectrometry (GC/MS) or liquid chromatography tandem mass spectrometry (LC-MS/MS) to obtain a unique fingerprint-like match of the chemical for conclusive identification. The combination of both tests gives extremely accurate and forensically defensible results.

In clinical testing a large variety of compounds are tested and not all are detected via the screening EIA tests. All specimens are sent to confirmation testing regardless of the outcome of the screening tests to test for a larger variety of drugs and metabolites requested by the client and to confirm any positive screening results and prescribed medications.

Urine Drug Test Classifications

There are three kinds of urine drug tests (UDT). The first method, known as an immunoassay, is inexpensive and produces results rapidly. It does, however, have downsides. For example, it does not detect all opioids. It also occasionally produces false positives. A false positive happens when drug test results are positive, yet there has been no drug use.

If your initial test is positive, a confirmation test is known as gas chromatography/mass spectrometry (GC/MS), or liquid chromatography-tandem mass spectrometry (LC-MS/MS) is performed. The same process as the immunoassay is used to obtain a urine specimen for this type of test. Although GC/MS and LC-MS results are more expensive and take longer to generate. However, they rarely have false positives and are much more reliable. All types of drug testing have the potential to produce a false negative. This occurs when the test indicates a negative result despite the presence of drug usage. Both tests have the potential to miss same-day drug use.

Urine LCMS Test

UDT is often performed in two steps: an initial drug screen followed by confirmation or definitive testing for drugs/drug classes that tested positive. Immunoassay screens are frequently used as first-line assays since they may be performed at the point of care and are relatively inexpensive.

Immunoassays, however, have limits. Because most immunoassay screenings identify the presence of a drug class (e.g., opioids) rather than the particular substance (e.g., hydromorphone), determining compliance can be difficult. Furthermore, because they are designed to cross-react with several medicines within a drug class, the antibodies can also cross-react with drugs outside that drug class. This is especially true if the drugs are present in high enough concentrations, resulting in false positive results.

Because of these constraints, all positive specimens should be sent to more specialized, conclusive testing, such as (LC-MS/MS) or (GC-MS/MS) (GC-MS).

The sensitivity of immunoassays is also an issue. Most were developed for use in an emergency or for occupational drug testing and have higher cutoffs than are required to assess compliance. Furthermore, individual medications within each therapeutic class will cross-react with the antibody at varying concentrations, resulting in false negative results. To obtain acceptable sensi­tivity, some studies have proposed that negative screening results be validated by LC-MS/MS or GC-MS.

Why Use Keystone Laboratories For Urine Drug Testing

While there are many reasons to give a urine drug test, basically, it is to find out if the person has a drug or alcohol problem. The basic test used in urine toxicology testing only gives a positive or negative. The person will need to go on to have an LCMS Urine test to find out how much of what drugs are present. This test is more expensive and will take longer, but it is far more accurate. However, many people start with the basic urine toxicology as the first screen. It is, for the most part, very accurate, and most people just need to know a yes or no answer. Further testing is done if the answer is yes, but the person feels the positive was false or due to a medication they are on.

If you have more questions about urine drug testing, or the results of your LCMS urine test or urine toxicology test, Keystone Laboratories, Inc. would be happy to help. Our team of experts has been performing these sorts of tests for many years. These years of experience and the latest technology help us perform the most accurate testing in the area.

Frequently Asked Questions About Urine Drug Testing

Urine drug testing may be required in a variety of situations.

For example, if your primary care physician suspects you have a drug or alcohol problem, they may prescribe this test. If you’re confused, or your conduct appears weird or risky, an emergency department doctor may also request this test.

Many firms require prospective employees to submit to a urine drug test before being hired. One advantage of the urine drug test is that it can keep persons with drug issues out of positions that demand alertness and focus. For example, a drug-addicted truck driver or air traffic controller could jeopardize the safety of numerous people. Testing may also reduce the likelihood of on-the-job accidents.

Residents of drug and alcohol recovery programs are tested on a regular basis. This helps the people in treatment for drug or alcohol addiction stay sober. If you are on probation or parole for a drug or alcohol-related offense, the officer in charge of your case may order random drug tests to ensure your sobriety.

Finally, the tests can be used at home. A family member, for example, may request a loved one to take this test to confirm that they are not using drugs or alcohol. If you intend to utilize an at-home test, you should first check with your family doctor or another health expert. If the test is positive, they can advise you on how to proceed.

A urine drug test, also known as a urine drug screen or a UDS, is a painless test. It analyzes your urine for the presence of certain illegal drugs and prescription medications. The urine drug test usually screens for:

  • amphetamines
  • methamphetamines
  • benzodiazepines
  • barbiturates
  • marijuana
  • cocaine
  • PCP
  • methadone
  • opioids (narcotics)

Alcohol can also be included in screening tests, but it’s usually detected through breath tests rather than urine screens.

A urine drug test can help a doctor detect potential substance abuse problems. After a drug test identifies drugs you may be misusing, doctors can help you start a treatment plan. Taking urine drug tests throughout substance abuse treatment helps to ensure that the plan is working and that you’re no longer taking drugs.

You will likely take the urine drug test in a bathroom specifically prepared for drug testing. The test procedure includes the following steps:

  1. You will receive a specimen cup from the person administering the test.
  2. You’ll need to leave your purse, briefcase, or other belongings in another room while you take the test. You’ll also need to empty your pockets.
  3. In rare cases, a same-gendered nurse or technician will accompany you into the bathroom to make sure you follow all testing procedures. They should explain the reason for this type of supervised testing.
  4. Clean your genital area with a moist cloth that the technician provides.
  5. Urinate into the cup. You need to produce at least 45 milliliters for the sample.
  6. When you finish urinating, put a lid on the cup and bring it to the technician.
  7. The temperature of your sample will be measured to ensure that it’s in the expected range.
  8. Both you and the collector must keep visual contact with the urine specimen at all times until it’s been sealed and packaged for testing.

Contact Keystone Laboratories To Get The Testing Solutions Your Practice Deserves!

Our Happy Customers

    Darlene Silver


    Keystone Laboratories has always helped in the line of work I do. Great turn around times and any time I need something Wally Brown makes sure that my lab has it. Shout out to Brittney, my Keystone courier! She is prompt and makes sure my specimens are transported. Very professional and kind.

      Brandy Shook


      As a phlebotomist in a 14 provider office accurate and timely results are a must! Wally Brown is a super representative who always makes sure we have what we need. Keep up the good work Keystone Laboratories!!

        Derrick Sexton


        I had to use this lab for a work related drug screen and they were very professional and prompt. I would recommend Keystone Laboratories to a colleague for sure.

          Amanda Daves

          Asheville Recovery Center

          Keystone lab is dedicated to assisting individuals with all their laboratory needs. I have utilized keystone labs for over 5 years now. They are knowledgeable and professional throughout the process. I highly recommend them!

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