The Utility of Urine Drug Screening

Transcription

1 The Utility of Urine Drug Screening Treating Addiction, Saving Lives Sea Cruises Bye Tazmania, still far from New Zealand February 8 th, 2018 Mandy Manak, MD FASAM, ISAM, CSAM, MRO Medical Director, ICDO

2 Copyright 2017 by Sea Courses Inc. All rights reserved. No part of this document may be reproduced, copied, stored, or transmitted in any form or by any means graphic, electronic, or mechanical, including photocopying, recording, or information storage and retrieval systems without prior written permission of Sea Courses Inc. except where permitted by law. Sea Courses is not responsible for any speaker or participant s statements, materials, acts or omissions.

3 LEARNING OBJECTIVES 1. Appreciate Urine Drug Testing as a Risk Mitigation Strategy 2. Learn the two types of Urine Drug Screens 3. Understand which and what to order on UDS 4. Interpret UDS results with more confidence 5. Understand when to do further testing of positive (and negative) UDS 6. Develop a plan for urine drug screening in the office

4 Canadian Guidelines Risk Mitigation Expert Guideline 6: Urine Drug Screening Baseline UDS for starting or receiving opioids Repeated UDS based on risk Ask about all medications, drugs recently taken, understand UDS, false positive, false negative

5 Types of Urine Drug Tests 1. Qualitative (Screening) Assays Identifies drugs/metabolites with variable specificity and sensitivity by drug class Either Point of Care or at the Lab 2. Quantitative (Confirmatory) Assays Identifies and quantifies individual drugs/metabolites with high specificity and sensitivity with defined cuttoff limits Only at the Lab

6 What s in a UDS? Point of care testing now available and reliable for: Opiates Benzos (except Clonazepam) Cocaine Amphetamines *** Methamphetamines Oxycodone EtOH Methadone (EDDP) Fentanyl Buprenorphine MDMA But Not Hydromorphone!

7 Metabolism of Opioids

8 UDS LIMITATIONS Opiates Codeine, Morphine, Heroin (6-MAM morphine), Hydrocodone, Hydromorphone, poppy seeds Cocaine Benzoylecgonine, highly specific Oxycodone Oxycodone Benzos Clonaz not detected Methadone (Metabolites) EDDP, need to request Fentanyl Need to ask specifically Hydromorphone No Immunoassay, only GCMS Amphetamine/Methamph need to request LOTS of cros reaction (cold medication, ephedrine, pseudoephedrine) THC Nabilone (Cesamet does not contain THC and is NOT detected in UDS) Marinol and Sativex are +

9 UDS LIMITATIONS Useful for assessing what the patient is taking What is NOT in the urine is just as important as what is present Hydromorphone is variably detected (under opiate ) Fentanyl is NOT detected in all kits requires a specific EIA Some benzos are variably detected the EIA used is the antibody for diazepam clonazepam may not show up Sertraline and citalopram can give a false positive for benzos Tests do not tell how much is being used or the frequency of use Cannot distinguish if patient is taking it as directed.

10 Substance Urine Blood Alcohol Amphetamines (except meth) 3 5 days via ethyl gluconoride (EtG) metabolite or 6-24 hours via traditional method 12 hours 1 to 3 days 12 hours Methamphetamine 3 to 5 days 1-3 days MDMA 4 days 25 hours Barbiturates (except phenobarbital) 2 to 3 days 1 to 2 days Phenobarbital 2 to 3 weeks 4 to 7 days Benzodiazepines Cannabis Cocaine Therapeutic use: 3 days. Chronic use (over one year): 4 to 6 weeks Single use: 1-6 days Weekly use: 3-9 days Daily use: 7-30 days 2 to 4 days with exceptions for certain kidney disorders 6 to 48 hours 2-3 days after infrequent use, up to 2 weeks after frequent use 24 hours Codeine 1 day 12 hours Morphine 2 days 6 hours Heroin 3 to 4 days 6 hours LSD 24 to 72 hours (however tests for LSD are very uncommon) 0 to 3 hours Methadone 3 days 24 hours PCP 3 to 7 days for single use; up to 30 days in chronic users 1 to 3 days

11 What does a positive UDS result really mean? Patient is compliant/adherent (took prescribed drug as directed) Patient added drug to urine after collection Patient took one dose prior to collection (but really non-compliant) Patient took another drug which also crossreacts with Ab Test Collection or Lab error/mix-up False positive

12 What does a Negative UDS result really mean? Patient is NOT compliant/adherent Patient took the drug less than prescribed (PRN) Altered pharmacokinetic variables Drug not absorbed Altered metabolism or elimination Diluted or adulterated sample Test doesn t x-react with drug of interest (ie oxycodone not picked up on opiate screen) Collection or Lab error/mix-up False negative Drug present, but below cutoff/detection limit

13 Limitations of Immunoassay False Negative and Detection Limits Variables Assay Cuttoff Assay Vendor Drug formulation/dose Pt pharmacokinetics Sample type Collection time from LD Specimen integrity/quality

14 Limitations Interferences Classic adulterants bleach, soap, liquid drain cleaner, white vinegar, glutaraldehyde, sodium nitrite, and pyridinium chlorochromate. Commercial adulterants, Urine Luck version 6.3, Stealth, Clean-X, Klear, Purafyzit, Instant Clean, Krystal Kleen, and UR n Kleen. Klear: is made of nitrite and affects the tetrahydrocannibinol (THC) confirmation process but not the immunoassay process.

15 Limitations Adulteration Diluting sample (artificially and biologically) Check SG and ph Using someone else s sample Use thermometers Use bluing liquid in toilets Observed sample collection

16 Oh, oh...not what I was expecting Retake history of medication/drug use in past week non-accusatory Advise patient of false positive and false negative Give patient opportunity to address any positive (and negative) results Ensure not lab error Request confirmation ON SAME SAMPLE

17 Confirmatory Testing GC/MS or LC/MS Very Specific, highly sensitive Still have issues related to drug presence vs impairment and intoxication due to drug Still have issues related to sample adulteration

18 Alcohol use Considered to be much more troublesome and much more widespread. Physicians frequently prescribed morphine to alcoholics without knowing how much they drink. Need to order EtOH specifically (24 hrs only)

19 Urine Drug Screen 1. GC Mass Spectroscopy 2. Or Thin Layer Chromotography 3. Hydromorphone 4. Salicylate Level 5. EthOH level 6. Acetaminophen Level for as needed confirmation

20 Case 57 M w/ chronic low back pain for 15 years after being thrown out of a jeep After 8 weeks pt still experiencing significant pain that is negatively affecting function; you start opioids (MSContin 15 mg TID titrated to 30 mg TID) to good effect: improved pain and function One month later, routine UDT positive for cocaine and Opiates

21 What was done/should have been done in advance Comprehensive approach to high-quality management of chronic pain Treatment agreement: discussion with pt about risk and benefits Fair warning that UDTs would be done Fair warning that + UDT might mean discontinuing opioids Practice-wide decision about how treatment agreement violations handled

22 What to do now? Get GC/MS confirmation of any unexpected result (if confirmed) Talk to patient, reveal result of test, ask him what he used, how long, how much, etc Show empathy but do not allow patient to dispute results Show empathy but do not allow patient to shift blame: I did it because my pain was out of control/you are not treating my pain Based on practice policy, begin opioid taper (1-2 week follow up with rudt) Consider addiction referral based on your assessment

23 Summary Identifies more misuse than self-report or physician impression Which test to order? Immunoassay as screen Lab or POC Gas chromotography/mass spectroscopy for confirmation recommend doing this any time you get an unexpected result Always ask and document recent intake before sending test

24 How to discuss UDT This is our routine practice. We want to ensure your safety.

25 Audience Survey How often do you think a UDS should be done? Consider risk: For opioid misuse or addiction Aberrant drug-related behaviour More frequently for higher risk (Q 2-4 wks) Less frequently for low risk (1-4 times/yr)

26 Audience Survey Should you do RANDOM UDS? Consider risk: Random Testing for high risk Preselect dates and have MOA call Allow 24 hrs for patient to provide sample

27 Audience Survey Should you collect UDS at every visit? OK to collect at every visit, but better to collect at SOME visits Random Testing for high risk

28 Pearls You are not a police officer Your office requires a standard procedure for UDS UDS is an imperfect tool with many limitations Can still be a useful clinical tool Need to clinical reasoning with interpretation Document Meds/drugs hx UDS interpretation Plan for action

29 Thank you