Urine Drug Testing Lab in Los Angeles
Urine drug testing for Los Angeles healthcare facilities
Centra Diagnostics is a urine drug testing lab in Marina Del Rey that serves healthcare facilities across Los Angeles County. Your staff collect the specimen on site. We pick it up, screen it, and confirm results by LC-MS/MS. The current menu confirms 81 drugs and metabolites, and results reach your EMR within 24 hours.
We work with employers, physicians, psychiatrists, behavioral health programs, substance use treatment facilities, urology, general medicine and women’s health practices. Every account gets onboarding, staff training and a dedicated account manager.
Screening and confirmation: two steps, two cutoffs
A urine drug test at Centra runs in two stages. The screen is a fast first pass that checks for 13 drug targets, including alcohol, amphetamine, benzodiazepines, buprenorphine, cocaine metabolites, heroin (6-MAM), methadone, opiates, oxycodone, THC and ethyl glucuronide.
Confirmation uses liquid chromatography-tandem mass spectrometry (LC-MS/MS). It identifies the exact drug or metabolite, not just the drug class. That matters when a result affects a treatment plan, a prescription or a patient’s standing in a program.
The two stages use different cutoff levels because they answer different questions. The screen asks whether a class is likely present. Confirmation asks which compound it is and at what level. Read more about the method on our LC-MS/MS technology page.
Specimen validity checks on every urine sample
Specimen validity testing confirms the sample is a normal human urine specimen that has not been diluted or altered. Centra measures three markers:
- Creatinine, which flags dilution
- pH, which flags possible adulterants
- Specific gravity, which flags samples that are too dilute or too concentrated
A result is only as useful as the specimen behind it. Validity checks give your clinicians confidence that a negative is a true negative.
What our urine toxicology panel confirms
The LC-MS/MS menu covers 81 analytes in 31 drug classes. Highlights that matter most to treatment and behavioral health programs:
| Category | Confirmed analytes |
|---|---|
| Fentanyl and additives | Fentanyl, norfentanyl, xylazine, 4-hydroxy xylazine |
| Medication-assisted treatment | Buprenorphine, norbuprenorphine, methadone, EDDP, naltrexone, naloxone |
| Opiates and opioids | Codeine, morphine, hydrocodone, hydromorphone, oxycodone, noroxycodone, oxymorphone, tramadol, tapentadol, 6-MAM |
| Kratom | Mitragynine, 7-hydroxymitragynine |
| Synthetic drugs | Synthetic cannabinoids (JWH-210, JWH-250, UR-144, XLR-11 metabolites), MDPV, methylone, mephedrone |
| Alcohol biomarkers | Ethyl glucuronide (EtG), ethyl sulfate (EtS) |
| Psychiatric medications | Citalopram, fluoxetine, paroxetine, sertraline, bupropion metabolite, aripiprazole, risperidone, lurasidone, quetiapine, olanzapine |
| Sedatives and others | Seven benzodiazepine analytes, barbiturates, zolpidem, gabapentin, pregabalin, muscle relaxants, ketamine |
See every analyte on the full testing directory.
Urine or oral fluid drug testing?
Centra offers both. Urine is the standard specimen for most monitoring programs and covers the full menu above. Oral fluid testing is an alternative when a directly observed collection is easier to arrange. Your account manager can help you choose the right specimen type for each patient population.
How urine drug testing works with Centra
- Onboarding and training. Your account representative trains staff on sample collection, requisition forms and pickup scheduling. Our IT team connects results to your EMR.
- Specimen pickup. Book a pickup window between 8 a.m. and 6 p.m. through the Schedule a Pickup form.
- Testing. Specimens are screened, validity-checked and confirmed by LC-MS/MS.
- Results in 24 hours. Reports upload to your EMR, and we walk authorized staff through them.
- Ongoing support. Your account manager visits at least twice a month.
Read the full testing process, or see how we support addiction treatment programs and employers.
Urine drug testing FAQs
How long do urine drug test results take?
Centra uploads results to your facility’s EMR system within 24 hours of testing. Your account team then reviews the report with authorized staff so the findings are clear.
What drugs does a urine drug test detect at Centra?
The current menu screens for 13 drug targets and confirms 81 drugs and metabolites by LC-MS/MS across 31 drug classes. That includes fentanyl, xylazine, kratom, synthetic cannabinoids, buprenorphine, methadone, benzodiazepines, alcohol metabolites and common psychiatric medications.
What is specimen validity testing?
Specimen validity testing checks that a urine sample is a normal human specimen that has not been diluted or altered. Centra measures creatinine, pH and specific gravity on urine specimens.
Why are screening and confirmation cutoff levels different?
A screen is a fast first pass that flags a drug class at a set threshold. Confirmation by LC-MS/MS identifies the exact drug or metabolite and measures it at a lower, more specific level. The two steps answer different questions, so they use different cutoffs.
Does Centra offer oral fluid drug testing?
Yes. Centra offers both urinalysis and oral fluid testing, analyzed with the same LC-MS/MS technology.
How does my facility schedule a specimen pickup?
Use the Schedule a Pickup form on the Contact page and choose a pickup window between 8 a.m. and 6 p.m. Requests sent after 3 p.m. Pacific are handled the next business day.
Ready to Speak to an Expert?
Whether you’re a healthcare provider looking for a trusted diagnostics partner or a patient seeking accurate results, Centra Diagnostics is here for you.
