Home Products Most Popular Contact
No items in your cart.
The page below is a sample from the LabCE course The Toxicology Laboratory's Role in Pain Management: Testing for Opiates. Access the complete course and earn ASCLS P.A.C.E.-approved continuing education credits by subscribing online.

Learn more about The Toxicology Laboratory's Role in Pain Management: Testing for Opiates (online CE course) »
How to Subscribe
MLS & MLT Comprehensive CE Package
Includes 128 CE courses, most popular
$95 Add to cart
Pick Your Courses
Up to 8 CE hours
$50 Add to cart
Individual course$20 Add to cart

Confirmation of Positives

A confirmatory test is often ordered or automatically reflexed when a positive drug screen is encountered, but not all positive DOA screens need to be confirmed. For example, if a patient admits to using THC and the urine THC test is positive, the clinician can stop there; there is no need to spend time and money confirming something that is not deemed suspicious. However, when a screen gives an unexpected result or when we need to know which particular drugs are present, as in the case of pain management, confirmatory testing is necessary.
Confirmatory testing is performed using gas chromatography and mass spectrometry (GC/MS) or liquid chromatography with tandem mass spectrometry (LC-MS/MS). Unlike immunoassays, a GC-MS or LC-MS/MS instrument looks for specific chemical compounds. Mass spectrometry techniques can produce quantitative results, although not all laboratories report quantitative results. In most cases, the clinician is only looking for the identity of the drug and not the quantity.