Monday, October 14, 2019

Urine Drug Screens and False Positives in Correctional Nursing

One thing I had not even considered until I was in Correctional Nursing was the possibility of false positives with drug screening.

Image result for drugs  

I've never taken any drugs (over the counter or by prescription) on a regular basis, so when I had to take drug tests for jobs - I never agonized over it or even gave it a second thought; but now, since I have been working within the Correctional Nursing field, urine drug screens are a pretty regular part of the work day, and the inmates we are testing think about it a lot.

Inevitably, when a screen comes up with a positive (especially with brand new inmates for my facility), they come up with some reasoning as to why it's positive - some make you think, some make you wonder whether or not they are still under the influence because they are so far-fetched. This is where a nurses critical thinking skills should kick in.

Image result for urine cup mckesson

At our facility we use the One Step Drug Screen Test. It's a 14 panel drug screen that tests a variety of substances in the urine. I used the informational insert, coupled it with the more common drugs we see here in my area and put together this graph for the Correctional Officers and medical staff to be able to quickly glance through when a urine drug screen is administered. It shows the short name from the dip stick, the class of drug it is testing for, some common names for drugs that if they had been ingested would show a positive and finally a generalized timeline for how long the drug would pop positive for after ingestion.

Drug Names
(not all drug names are listed)
How Long After Ingestion it could Test Positive for
Dexedrine, Adderall, Dextroamphetamine, Methamphetamine, ProCentra, Dextrostat, Ritalin, Concerta, Vyvanse, Strattera, Speed, Benzedrine
1 to 2 days
Amytal, Butisol Sodium, Luminal, Nembutal, Phenobarbital, Seconal, Fioricet, Fiorinal, Brevital, Pentothal
2 days to 3 weeks
Diazepam, Valium, Xanax, Alprazolam, Klonopin, Clonazepam, Librium, Versed, Ativan, Lorazepam, Halcion, Restoril, Ambien, Sonata, Lunesta, ProSom, Restas, Zoldem, Serax
3 days to 6 weeks
6 hours to 2 days
Narcotic / Stimulant
2 to 4 days
2 days to 2 months
Analgesic / Opiate
3 days
1 to 2 days
1 to 2 days
Morphine, Codeine, Heroin, Vicodin, Norco, Hydrocodone, Lortab, Lorcet, Fentanyl, Dilaudid, Percocet, Demerol, Tramadol
2 days
1 day
Phencyclidine (PCP)
14 to 30 days
Narcotic Analgesic
Propoxyphene, Darvocet
3 days
Tricyclic Antidepressant
Elavil, Pamelor, Vivactil
1 to 3 days

                                             Image result for random excuse

Some of the random, but common, excuses for positive test results I've heard are below with some reasons why they cannot possibly be true.

I ate a bunch of poppy seeds right before being arrested!               

Image result for poppy seed"Poppy seeds, often found on bagels, rolls, and pastries have long been used as a defense against positive opiate test results encountered on a urine drug screen. It is known that poppy seeds do contain opiates - specifically morphine and codeine; however, content varies greatly depending upon seed source and processing. Food processing may lower the opiate levels in poppy seeds.Federal authorities who mandate drug testing for federal employees have raised the required morphine cutoff concentration from 300 to 2,000 ng/mL to reduce the number of opiate false positives due to poppy seed consumption. This level is current as of 2019."

My friends were smoking marijuana in the vehicle/house (etc.) and I breathed it in!                        

Image result for smoke"The argument of inhalation of "passive" pot smoke from being in a room with people smoking marijuana (cannabis) is not a valid excuse, as the cut-off concentrations for lab analysis (usually 50 ng/mL) are set well above that which might occur from passive inhalation."

I had a dental procedure recently! OR I was wearing a Lidocaine patch for pain (random day or week prior to incarceration)!                         

Image result for novocaine mckesson
"Procaine, Novocaine or Lidocaine use as a defense for cocaine abuse is not a valid excuse. If benzoylecgonine, the main metabolite of cocaine is detected in a drug test, the subject cannot claim that the result is a false positive due to Novocain administration, or any other "-caine" drug. Benzoylecgonine is only found in nature as a metabolite of cocaine, and there would be no other valid reason for its presence in a drug screen.2 As previously mentioned, confirmatory testing with GC-MS will identify individual drugs or metabolites in a sample, and almost eliminate the chance for a false positive result."

My personal favorite came from a woman whom had come into the hospital during one of my clinic cycles and gave birth to a baby boy, whom promptly started detoxing from what we found out was cocaine and Methamphetamines. She stated that the reason both herself and the baby were detoxing was because she was giving her boyfriend ("who does drugs all the time") multiple daily blowjobs and swallowing the ejaculate.
Image result for sperm                                
This is an invalid excuse as well - the amount of drug that could possibly be transferred in semen is so minuscule, she would have had to be swallowing literal bucket fulls of it for months on a daily basis.

Consequences of a false positive drug screen can be life altering. It can literally ruin a persons life in a multitude of ways. So doing your 'homework' as a correctional nurse can make a huge difference between an innocent person being wrongly accused and an illicit drug user being taken off the streets.

In this mindset, I found a graph from: that was posted/written in June of 2019 showing possible reasoning's for a false positive that are valid and included this with my educational packet concerning drug testing to my Correctional Officers and Medical Staff.
Substances that may interfere with drug testing:Reported false positive result:
amantadine (Osmolex ER)amphetamines
amitriptyline (Elavil, brand discontinued in US)LSD (lysergic acid diethyamide)
benzphetamine (Regimex)amphetamines
brompheniramine (Dimetapp)amphetamines and methamphetamines
bupropion (Aplenzin, Forfivo XL, Wellbutrin XL, Zyban)amphetamines and methamphetamines, LSD
carbamazepine (Carbatrol, Equetro, Tegretol)tricyclic antidepressants
chlorpromazine amphetamines and methamphetamines, methadone
clomipramine (Anafranil)methadone
coca leaf teacocaine
cocaine anesthetics, topicalcocaine
cyclobenzaprine (Amrix, Fexmid, Flexeril [brand discontinued in US])tricyclic antidepressants
cyproheptadinetricyclic antidepressants
dextromethorphan (Robitussin, Delsym, Nyquil, Triaminic)phencyclidine (PCP), opiates
diphenhydramine (Benadryl, Zzzquil), doxylamine (Unisom, Nytol) methadone, opiates, phencyclidine (PCP), tricyclic antidepressants
diet pillsamphetamines
desipramine (Norpramin)amphetamines
dronabinol (Marinol), nabilone (Cesamet)cannabinoids
efavirenz (Sustiva) - also found in many combination HIV medscannabinoids, benzodiazepines
ephedrine nasalamphetamines and methamphetamines
hemp oil marijuana (cannabinoids), tetrahydrocannabinol (THC)1,6
hydroxyzine (Vistaril)tricyclic antidepressants
ibuprofen, naproxen, tolmetin (NSAIDs)marijuana (cannabinoids), barbiturates, benzodiazepines1; Phencyclidine (PCP)
imipramine (Tofranil)phencyclidine (PCP)LSD
ketamine (Ketalar), possibly esketamine (Spravato), the S-enantiomer of racemic ketaminephencyclidine (PCP)
labetalol (Trandate)amphetamines
MDMA (illicit drug)amphetamines
meperidine (Demerol)phencyclidine (PCP)
mesoridazine (brand discontinued in US)phencyclidine (PCP)
methylphenidate (Adhansia XR, Aprensio XR, Concerta, Daytrana, Focalin XR, Ritalin, others)amphetamines
oxaprozin (Daypro)benzodiazepines
pantoprazole (Protonix), possibly other proton pump inhibitors (PPIs)tetrahydrocannabinol (THC)
phenylpropanolamine (brand discontinued in US)amphetamines and methamphetamines
phentermine (Adipex-P, Lomaira, Qsymia)amphetamines

promethazine (Phenergan [brand discontinued in US], Phenadoz, Promethegan)amphetamines and methamphetamines
pseudoephedrine (in behind the counter  nonprescription allergy and cold products such as Allegra-D, Clarinex-D, Mucinex-D)amphetamines
quetiapine (Seroquel, Seroquel XR)methadone, tricyclic antidepressants
quinolone antibiotic (ofloxacin, gatifloxacin)phencyclidine (PCP), opiates
ranitidine (Zantac 75, Zantac 150)amphetamines and methamphetamines
rifampin (Rifadin, Rifamate, Rimactane)opiates
selegiline (Eldepryl [brand discontinued in US], Emsam, Zelapar)amphetamines
sertraline (Zoloft) benzodiazepines
thioridazine (Thorazine)methadone, phencyclidine (PCP)
tramadol (Conzip, Ultram)phencyclidine (PCP)
trazodone (Desyrel)amphetamines and methamphetamines
trimethobenzamide (Tigan, Ticon)amphetamines
trimipramine (Surmontil)amphetamines
venlafaxine (Effexor XR)phencyclidine (PCP)
verapamil (Calan)methadone, other opiates

Hopefully you've found this post informational and entertaining! Let me know what you thought in the comments!! Any questions? Ask away!!

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  1. Protonix can create a false positive on your urine drug screen for THC. Wellbutrin can create a false positive for amphetamines. Although you would think in a correctional setting if you were legitimately taking those drugs they would know it and take that into account

  2. @ Sandy Klocinski - That is exactly what I mean by critical thinking by the Correctional Nurse!

    Three (3) Things:

    1 - The Probation / Parole Officers, Police Men and Correctional Officers whom are testing them do NOT usually know that these regularly prescribed medications could cause a false positive

    2 - In some correctional facilities sometimes illegal drugs sneak through the extensive initial searches that the staff completes prior to an inmate being put into general population (for instance if someone were to swallow something and then have it come out with their next bowel movement)- an inmate may or may not be actually on an illegal drug or it may be a bi-product of their medications; knowing that these certain drugs can cause false positives may be very beneficial in the investigation

    3 - Same scenario as number 2 but with a group or cell full of inmates all dropping positive for something on a random drug testing

    Thank You for your comment!!

  3. Wow so many things that can give false positives. The only one I knew about was the poppy seed muffins

  4. I never knew so many things could cause a false positive.

  5. Good to know of these, definitely will keep it in mind. It's important to note of the many meds that can trigger these false positives.