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You Can’t Fool the “Bladder Police”
Effective Use of Urine Drug Screening
Why Test?
• Accountability
• Create and maintain safe treatment
environment
• Compliance with licensing or policy
Collection
• Supervised or unsupervised
• When to collect
• Staff training
• Temperature monitored cups
• Adulterant testing
In-house Testing
• Cost
• Staff training
• Type of test kit
• Staff issues
• What to test for
• Client privacy
• When to test
Lab Testing
• Prescription
• Staff training
• What to test for
• Completing forms
• When to test
• Storage and pick
up
Testing – How it Works
• Drug Testing Systems
 One Test Systems
 Use immunoassay (IA) to detect the presence
of drugs and
 Are most often used for medical purposes in
clinical and rehabilitation settings
 Two Test Systems
 Commonly use immunoassay as an initial test
followed by a more specific confirmatory test
using a different technology and
 Are used for results requiring a high level of
certainty
John M. Mitchell
Immunoassays as an Initial Test in Drug
Testing. Center for Forensic Sciences
Testing – How it Works
What is an Immunoassay?
• An immunoassay is a biochemical test that
measures the concentration of a substance
in a liquid (a portion of a biological
specimen) using the reaction of an antibody
or antibodies to its antigen (drug)
John M. Mitchell
Immunoassays as an Initial Test in Drug
Testing. Center for Forensic Sciences
Testing – How it Works
What are Antibodies and
Antigens?
• Antibodies are a type of protein produced
by the immune system in response to
foreign substances (antigens)
• Antibodies bind to the antigen responsible
for their production
John M. Mitchell
Immunoassays as an Initial Test in Drug
Testing. Center for Forensic Sciences
Testing – How it Works
Antibodies:
• Usually harvested from
sheep or rabbits
• Usually IgG (represented
as a “Y”)
• Developed against classes
of drugs
• Recognize antigen (drug)
by its shape
Y
Immunoassay Principles I
Common end
Shape recognition end
John M. Mitchell
Immunoassays as an Initial Test in Drug
Testing. Center for Forensic Sciences
Testing – How it Works
Immunoassay Principles II
• Use Tagged Drug Targets
 Indicator (Tag) is bound to the target drug
 “Tag” may be
 an enzyme
 a fluorophore
 a particle
“Tag”
• Detection is based on competitive binding
 Antibodies bind with Drug in Sample OR
with Tagged Drug Targets
Drug
John M. Mitchell
Immunoassays as an Initial Test in Drug
Testing. Center for Forensic Sciences
Testing – How it Works
Immunoassay principles
• Sample WITH drug in it
• Add an antibody
• Incubate
Y
John M. Mitchell
Immunoassays as an Initial Test in Drug
Testing. Center for Forensic Sciences
Testing – How it Works
Immunoassay
Principles III
• Antibody binds drug in
the sample
• Add tagged drug target
• Little or no antibody
binding of the tagged
compound
• Little or no change in
signal
John M. Mitchell
Immunoassays as an Initial Test in Drug
Testing. Center for Forensic Sciences
Y
Testing – How it Works
Immunoassay Principles IV
•
•
•
•
Sample WITHOUT drug in it
Add an antibody
Incubate
Add tagged drug target
Y
John M. Mitchell
Immunoassays as an Initial Test in Drug
Testing. Center for Forensic Sciences
Testing – How it Works
Immunoassay Principles
• Antibody binds with the tagged
compound
• Binding causes change in signal
produced
John M. Mitchell
Immunoassays as an Initial Test in Drug
Testing. Center for Forensic Sciences
Testing – How it Works
Testing with Immunoassays
• Immunoassays are used to screen donor specimens for the
possible presence of a drug or a class of drugs
• These tests may be conducted on-site as part of the collection
process or in a laboratory or other facility
• On-site testing is normally conducted with a Point of Collection
Test (POCT) device
• Most testing is conducted in laboratories which have validated
procedures and validated analytical instrumentation
• Immunoassays allow some laboratories to test more than
10,000 donor specimens a day
John M. Mitchell
Immunoassays as an Initial Test in Drug
Testing. Center for Forensic Sciences
Testing – How it Works
Immunoassay Specificity
• Specificity is the affinity of an immunoassay for the
target drug
• Specificity is measured by cross reactivity:
 the response exhibited when an immunoassay
reacts with a compound other than the target
drug
• Specificity limits the conclusions that can be drawn
from immunoassay results
John M. Mitchell
Immunoassays as an Initial Test in Drug
Testing. Center for Forensic Sciences
Testing – How it Works
Low Specificity
• An immunoassay with low specificity will react with
many antigens (drugs) with similar structure
• Example: One Amphetamine immunoassay with a
cutoff of 300 ng/mL of D-Amphetamine gives a
positive result with:
 D,L-Amphetamine (300 ng/mL), Phentermine (400 ng/mL),
Tranylcypromine (500 ng/mL), Methamphetamine (1,000
ng/mL), Ephedrine (1,000 ng/mL), or Phenylpropanolamine
(1,000 ng/mL)
 Therefore, a positive result from this immunoassay test
would not prove use of amphetamine
John M. Mitchell
Immunoassays as an Initial Test in Drug
Testing. Center for Forensic Sciences
Tampering
• Diluting
• “Doping”
• Substitution
Tampering
• Diluting
 Hyper saturating the body with fluids to dilute metabolites
possibly below the 50 ng/mL threshold, depending on your
metabolism.
 AZO
 Certo
 Niacin
 QCarbo
 Vinegar
 XXtra Clean
 Fiber pills
 Quick Flush
 Ready Clean pills
 Terminator Gold
 Rapid Cleanse
 Clear Choice
 Detox Tea
 MC1
 Goldenseal
 Vale Triple Strength
Tampering
• “Doping”
 Adding different chemicals that defeat
immunoglobulin/antigen binding








Bleach (powdered)
Water
Ammonia
Blood
Draino
Goldenseal
Hydrogen Peroxide
Lemon Juice








Liquid Soap
Mary Jane’s SuperClean
13
Purifyit
Sodium Nitrate
Table Salt
Vinegar
Visine
WD 40
Tampering
• Substitution
 Concealed container
 Injection
 Catheterization
 Cigar containers/droppers
Tampering - Countermeasures
• Color
• Temperature
• Creatinine
• pH
• Specific gravity
False Positives
Generic
Efavirenz
Name Brand Possible False Positive
Sustiva
Positive for Cannabinoids
(THC) [Urinary
metabolite(s) only; parent
compound is non-reactive]
Flunitrazepam Rohypnol
Positive for
Benzodiazepines (BZO)
Lamotrigine
Lamitcal
Positive for Phencyclidine
(PCP)
False Positives
Generic
Name
Brand
lVick's
Methamphetamine Inhaler
HCL
Phenytoin
Dilantin
Possible False Positive
Positive for
Methamphetamine (mAMP)
Possible Positive for
Barbiturates (BAR) Urinary
metabolite(s) only; parent
compound is non-reactive
False Positives
Generic
Procaine
Ranitidine
Name Brand
Novocain
Possible False Positive
Positive for Opiates (OPI,
MOP)
Pylorid, Zantac Positive for
Methamphetamine (M-AMP)
Urinary metabolite(s) only;
parent compound is nonreactive
False Positives
Generic
Sertraline
Name Brand
Zoloft
Venlafaxine Effexor or
Effexor XL
Possible False Positive
Potential Positive for
Benzodiazepines (BZO)
Potential Positive for
Phencyclidine (PCP)
False Positives
• All positives require clinical intervention
• Review clients medications before
engaging in a clinical intervention
• If a client reports taking a medication
that may cause a false positive, a
confirmatory test should be completed
False Negatives
• Time elapsed since use
• Improperly obtained or secured
specimen
• Tampered sample
Detection Times
Drug
Amphetamines
Barbituates
Approximate
Detection Time
2-4 days
Short-Acting (Secobarbital) 1 day
Long-Acting (Phenobarbital) 2-3 weeks
Benzodiazepines
3-7 days
Detection Times
Drug
Approximate
Detection Time
Cannabinoids
3-30 days
Cocaine
2-4 days
Codeine
2-5 days
Euphorics (MDMA, Psilocybin) 1-3 days
Detection Times
Drug
Approximate
Detection Time
LSD
1-4 days
Methadone
3-5 days
Methaqualone
14 days
Opiates
2-4 days
Phencyclidine (PCP)
2-4 days
Detection Times
Drug
Phenobarbital
Propoxyphene
Steroids (Anabolic)
Oral
Parenterally
Approximate
Detection Time
10-20 days
6 hours to 2 days
14 days
1 month
Clinical Interventions
•
•
•
•
Drug testing is a clinical intervention
Upon admission, always explain the role of drug testing
Drug testing may be scheduled, random, or suspicious
Prior to securing the urine, ask the client about changes in
medication and if the client has used
• Always explain the “why” of a particular drug test
• If the drug test is “suspicious,” discuss the behaviors that
brought about suspicion
• Review test results with client immediately upon receipt,
regardless of result
Clinical Interventions
• Negative drug screen
 Congratulate the client
 Review what drugs were tested for
 Ask the client about use of drugs not tested
 Ask about issue/problems when the sample was secured
Clinical Interventions
• Positive drug screen
 Tell the client you have the results and ask if the client
has anything to share
 Review what drugs were tested for and indicate what
was positive
 Allow the client time to respond
 Ask the client about use of drugs not tested
 Ask about when the client used, the circumstances
 Review/discuss consequences
 If discharge, make appropriate referral
 If no discharge, develop relapse prevention plan
Resources
Resources
• Collins, Jennifer. Laboratory Perspective on Additional
Drug Testing and Associated Costs. MEDTOX
Laboratories, Inc.
• Mitchell, John M. Immunoassays as an Initial Test in
Drug Testing. Center for Forensic Sciences . RTI
International
• TROUBLESHOOTING GUIDE DRUGS OF ABUSE.
Innovacon, Inc. San Diego, CA
• http://www.drug-test-facts.com
• http://www.drugabuse.gov/nidahome.html
• http://www.drugdetection.net/drug.htm
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