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Laboratory Testing Cutoffs & Methods

The following is an explanation of RTL's urine screening and confirmation procedures/cutoff levels. The routine cutoff levels listed below may periodically change.

Comprehensive Panel Screen

The following list provides screening detail for the Comprehensive Drug Test panel. RTL screens urine specimens by enzyme assay (EA), enzyme immunoassay (EIA), and liquid chromatography-tandem mass spectrometry (LC-MS/MS).

Screen Reporting Levels By Procedure

Drug Method Cutoff
Alcohol (Ethanol) EA 0.04 g/dL
Amphetamines
  - Amphetamines
  - Methylenedioxyamphetamine (MDA)
  - Methylenedioxymethamphetamine (MDMA)
  - Methylenedioxyethylamphetamine (MDEA)		  
EIA
LC-MS/MS
LC-MS/MS
LC-MS/MS		  
1000 ng/mL
250 ng/mL
250 ng/mL
250 ng/mL
Anticonvulsants
  - Carbamazepine and/or Metabolite
  - Oxcarbazepine Metabolite		  
LC-MS/MS
LC-MS/MS		  
100 ng/mL
100 ng/mL
Antidepressants
  - Amitriptyline/Nortriptyline
  - Bupropion Metabolite
  - Citalopram/Escitalopram
  - Desipramine/Imipramine
  - Doxepin
  - Fluoxetine and/or Metabolite
  - Maprotiline
  - Paroxetine
  - Sertraline
  - Trazodone/Nefazodone and/or Metabolite
  - Venlafaxine Metabolite
  
LC-MS/MS
LC-MS/MS
LC-MS/MS
LC-MS/MS
LC-MS/MS
LC-MS/MS
LC-MS/MS
LC-MS/MS
LC-MS/MS
LC-MS/MS
LC-MS/MS		  
100 ng/mL
250 ng/mL
150 ng/mL
100 ng/mL
100 ng/mL
150 ng/mL
100 ng/mL
150 ng/mL
150 ng/mL
Qualitative
100 ng/mL
Barbiturates EIA 200 ng/mL
Benzodiazepines
  - Alprazolam Metabolite
  - Clonazepam Metabolite
  - Flunitrazepam Metabolite
  - Flurazepam Metabolite
  - Lorazepam
  - Midazolam Metabolite
  - Nordiazepam
  - Oxazepam
  - Temazepam
  - Triazolam Metabolite
  
LC-MS/MS
LC-MS/MS
LC-MS/MS
LC-MS/MS
LC-MS/MS
LC-MS/MS
LC-MS/MS
LC-MS/MS
LC-MS/MS
LC-MS/MS		  
50 ng/mL
50 ng/mL
50 ng/mL
50 ng/mL
50 ng/mL
50 ng/mL
50 ng/mL
50 ng/mL
50 ng/mL
50 ng/mL
Cocaine EIA 300 ng/mL
Methylphenidate LC-MS/MS 50 ng/mL
Narcotics/Opiates
  - Buprenorphine
  - Butorphanol Metabolite
  - Codeine
  - Fentanyl
  - Hydrocodone
  - Hydromorphone
  - Ketamine Metabolite
  - Meperidine Metabolite
  - Methadone
  - Morphine
  - Nalbuphine
  - Oxycodone/Oxymorphone
  - Pentazocine
  - Propoxyphene
  - Tramadol and/or Metabolite
  
EIA
LC-MS/MS
LC-MS/MS
LC-MS/MS
LC-MS/MS
LC-MS/MS
LC-MS/MS
LC-MS/MS
EIA
LC-MS/MS
LC-MS/MS
LC-MS/MS
LC-MS/MS
EIA
LC-MS/MS		  
5 ng/mL
Qualitative
100 ng/mL
5 ng/mL
100 ng/mL
100 ng/mL
25 ng/mL
25 ng/mL
150 ng/mL
100 ng/mL
100 ng/mL
50 ng/mL
100 ng/mL
300 ng/mL
100 ng/mL
Phencyclidine (PCP) EIA 25 ng/mL
Sedative/Hypnotic Agents
  - Carisoprodol/Meprobamate
  - Zolpidem Metabolite

LC-MS/MS
LC-MS/MS
200 ng/mL
10 ng/mL
THC (Marijuana) EIA 50 ng/mL

Comprehensive Panel Confirmation

The following list provides confirmation detail for the Comprehensive Drug Test panel. RTL confirms urine specimens by gas chromatography-mass spectrometry (GC-MS), liquid chromatography- tandem mass spectrometry (LC-MS/MS) and/or gas chromatography- flame ionization detector (GC-FID).

Confirmation Cutoff Levels By Procedure
Drug Method Cutoff
Alcohol (Ethanol) GC-FID 0.02 g/dL
Amphetamines
  - Amphetamine
  - Methamphetamine
  - Methylenedioxyamphetamine (MDA)
  - Methylenedioxymethamphetamine (MDMA)
  - Methylenedioxyethylamphetamine (MDEA)
LC-MS/MS
LC-MS/MS
LC-MS/MS
LC-MS/MS
LC-MS/MS
250 ng/mL
250 ng/mL
250 ng/mL
250 ng/mL
250 ng/mL
Anticonvulsants
  - Carbamazepine
  - 10,11-Dihydroxycarbazepine
  - Oxcarbazepine
  - 10-Hydroxycarbazepine		  
GC-MS
GC-MS
GC-MS
GC-MS		  
100 ng/mL
Qualitative
100 ng/mL
100 ng/mL
Antidepressants
  - Amitriptyline
  - Nortriptyline
  - Hydroxybupropion
  - Citalopram/Escitalopram
  - Desipramine
  - Imipramine
  - Doxepin
  - Desmethyldoxepin
  - Fluoxetine
  - Norfluoxetine
  - Maprotiline
  - Paroxetine
  - Sertraline
  - Norsertraline
  - mCPP
  - Hydroxy-mCPP
  - Trazodone
  - Hydroxytrazodone
  - Venlafaxine
  - O-Desmethylvenlafaxine		  
LC-MS/MS
LC-MS/MS
GC-MS
GC-MS
LC-MS/MS
LC-MS/MS
LC-MS/MS
LC-MS/MS
GC-MS
GC-MS
GC-MS
GC-MS
GC-MS
GC-MS
GC-MS
GC-MS
GC-MS
GC-MS
LC-MS/MS
LC-MS/MS		  
25 ng/mL
25 ng/mL
250 ng/mL
150 ng/mL
25 ng/mL
25 ng/mL
25 ng/mL
25 ng/mL
150 ng/mL
150 ng/mL
100 ng/mL
150 ng/mL
150 ng/mL
150 ng/mL
100 ng/mL
Qualitative
Qualitative
Qualitative
100 ng/mL
100 ng/mL
Barbiturates
  - Amobarbital
  - Butabarbital
  - Butalbital
  - Pentobarbital
  - Phenobarbital
  - Secobarbital
GC-MS
GC-MS
GC-MS
GC-MS
GC-MS
GC-MS		  
200 ng/mL
200 ng/mL
200 ng/mL
200 ng/mL
200 ng/mL
200 ng/mL
Benzodiazepines
  - alpha-Hydroxyalprazolam (Alprazolam)
  - 7-Aminoclonazepam (Clonazepam)
  - 7-Aminoflunitrazepam (Flunitrazepam)
  - 2-Hydroxyethyl flurazepam (Flurazepam)
  - Lorazepam
  - alpha-Hydroxymidazolam (Midazolam)
  - Nordiazepam
  - Oxazepam
  - Temazepam
  - alpha-Hydroxytriazolam (Triazolam)		  
LC-MS/MS
LC-MS/MS
LC-MS/MS
LC-MS/MS
LC-MS/MS
LC-MS/MS
LC-MS/MS
LC-MS/MS
LC-MS/MS
LC-MS/MS		  
50 ng/mL
50 ng/mL
50 ng/mL
50 ng/mL
50 ng/mL
50 ng/mL
50 ng/mL
50 ng/mL
50 ng/mL
50 ng/mL
Cocaine LC-MS/MS 100 ng/mL
Methylphenidate GC-MS Qualitative
Narcotics/Opiates
  - Buprenorphine
  - Norbuprenorphine
  - Butorphanol
  - Hydroxybutorphanol
  - Codeine
  - Fentanyl
  - Hydrocodone
  - Hydromorphone
  - Ketamine
  - Norketamine
  - Dehydronorketamine
  - Normeperidine
  - Methadone
  - Methadone Metabolite (EDDP)
  - Morphine
  - Nalbuphine
  - Noroxycodone
  - Oxycodone
  - Oxymorphone
  - Pentazocine
  - Propoxyphene
  - Norpropoxyphene
  - Tramadol
  - O-Desmethyl-cis-Tramadol		  
LC-MS/MS
LC-MS/MS
GC-MS
GC-MS
LC-MS/MS
GC-MS
LC-MS/MS
LC-MS/MS
GC-MS
GC-MS
GC-MS
GC-MS
LC-MS/MS
LC-MS/MS
LC-MS/MS
GC-MS
LC-MS/MS
LC-MS/MS
LC-MS/MS
GC-MS
GC-MS
GC-MS
LC-MS/MS
LC-MS/MS		  
0.5 ng/mL
2 ng/mL
5 ng/mL
Qualitative
100 ng/mL
5 ng/mL
100 ng/mL
100 ng/mL
5 ng/mL
5 ng/mL
25 ng/mL
50 ng/mL
100 ng/ml
100 ng/mL
100 ng/mL
250 ng/mL
50 ng/mL
50 ng/mL
50 ng/mL
250 ng/mL
200 ng/mL
200 ng/mL
100 ng/mL
100 ng/mL
Phencyclidine (PCP) GC-MS 5 ng/mL
Sedative/Hypnotic Agents
  - Carisoprodol
  - Meprobamate
  - Zolpidem
  - Carboxyzolpidem
LC-MS/MS
LC-MS/MS
LC-MS/MS
LC-MS/MS
100 ng/mL
100 ng/mL
1 ng/mL
10 ng/mL
THC (Marijuana)
  - THC-COOH (Marijuana)
  - THC-COOH/Creatinine Ratio
LC-MS/MS
Calculation
5 ng/mL

Urinalysis Adulteration Examination

RTL's Standard Operating Procedures (SOP's) require that each urine specimen be examined for signs of adulteration. This examination includes the following


To learn more about RTL's laboratory drug tests call:

800.255.2159

Contact Us

Laboratory: 800-255-2159

Products: 877-444-0049

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