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DRUGS FALSE POSITIVES AND FALSE NEGATIVES
What causes a false positive on a drug screen?
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Immunoassay tests are inexpensive, quick and effective, but they aren’t fail-safe. Unfortunately, inaccurate results on immunoassay tests can happen. Sometimes this can be due to a mishap or error at a laboratory, but certain medications can cause false positives as well.

“False positives can happen when a test detects a substance that isn’t actually there,” said Georgina Rubal-Peace, PharmD, director of Medication Use Policy at Banner Health in Tucson, AZ. “These imposter substances can be byproducts of prescription or over-the-counter medicines, nutritional supplements and sometimes in certain foods. They may not be illegal, but they inaccurately appear as such.”

Makers of immunoassay tests continually refine the sensitivity of the test panels to reduce the likelihood of false positive test results but with the growing number of substances – particularly prescription drugs – it may always be an issue with immunoassay testing.

Things that can cause a false positive test result on a drug test
The following is a list of over-the-counter, prescription medications and foods that have the potential to cause unexpected results:

Amphetamine false positives
ADHD (attention deficit hyperactivity disorder) medications like methylphenidate (Ritalin)
Antidepressants like bupropion (Wellbutrin), fluoxetine (Prozac) and trazadone (Desyrel)
Beta blockers like labetalol (Trandate)
Diet pills like phentermine (Adipex-P)
Medication to treat nausea and vomiting like phenothiazines (Promethazine)
Over-the-counter cold, sinus and nasal decongestants like ephedrine and pseudoephedrine (Sudafed) and Vicks inhaler
Barbiturates
Pain medication like ibuprofen (Advil/Motrin) and naproxen sodium (Aleve)
Sleep aids like doxylamine (Unisom)
Benzodiazepine
Pain medication like ibuprofen
Selective serotonin reuptake inhibitors (SSRIs) like sertraline (Zoloft), which can be used to treat depression, post-traumatic stress disorder (PTSD), obsessive-compulsive disorder (OCD), social anxiety disorder and panic attacks.
Cannabinoid
Cannabidiol (CBD) oil
Hemp food products
HIV medication like efavirenz (Sustiva)
Pain medication like ibuprofen
Proton-pump inhibitors, specifically pantoprazole (Protonix), may cause false-positive for THC
Some vitamin B supplements that come from hemp seed oil
Cocaine
Coca tea
Opioids and opiates
Quinoline antibiotics used to treat bacterial infections like levofloxacin (Levaquin) and ofloxacin
Anti-psychotic medications like quetiapine (Seroquel)
Over-the-counter antihistamines like diphenhydramine (Benadryl)
Poppy seeds
Testing positive for THC while using CBD
There is a potential risk of testing positive for THC, the psychoactive ingredient in marijuana, when using cannabidiol, or CBD. CBD itself will not cause a false positive drug test, however, products made from hemp can contain small amounts of THC that can show up on a urine drug test.

Hemp is any part of a cannabis plant that contains 0.3% THC or less. CBD products made from hemp could have small amounts of THC in them even if it is not listed on the label. This means that people who use CBD regularly could build up high enough THC levels in their body to test positive.

Another issue has to do with product quality. Reports have shown that some CBD products contain varying amounts of THC, some so high that they cannot be explained by legal amounts of hemp. Patients who are thinking about taking CBD products should talk to their health care providers first.

Should I stop taking medications or 'detox' before a drug test?
Don’t stop taking any medications without prior approval and guidance from your health care provider. As well, avoid any quick-fix remedies or detoxes that “make promises” to help you pass drug tests. Their clams don’t hold up — some can even be harmful.

“Remedies purported as magic detoxes on social media, such as taking niacin before a drug test or goldenseal, an herb in the buttercup family, have not been shown to ‘trick’ a drug test and may cause liver injury in high doses,” Dr. Rubal-Peace said.

Proof-positive: How to handle your drug test
If you regularly use certain medications, supplements or foods that could potentially trigger a false positive result, let whoever is performing the test know ahead of time. Be prepared to bring or provide a list to the laboratory. Getting in front of the issue will protect you from a potential false positive.
- Some cut-off levels in other cups might be very high and will not pick up any traces.
- Please perform a seperate test with just water. If the cup is not positive with water, there can be several reasons.
- Check cross reactions (shown on left side)
** A faint line is considered a line**
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Fentanyl (FYL)False PositiveFalse Negative
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MDMA,Vyvanse, ziprasidone, Diphenhydramine, Poppy seeds, Codeine, Methamphetamine, Trozodone, risperidone and its metabolite 9-hydroxrisperidone share an intramolecular alkylated piperidine acetylfentanyl, Loperamide, Lidocaine
Doxylamine, quinolone antibiotics, rifampin, Ciprofloxacin, moxifloxacin, and norfloxacin,
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Alcohol (EtG)False PositiveFalse Negative
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mouthwash, large amounts of appe juice, hand sanitizer, Nyquil or other cold medications, Kombucha
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Opioids (OPI)False PositiveFalse Negative
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Quinolones, Verapamil, Poppy Seeds, Benadryl, everything bagel, Tylenol 3, Tylenol with Codeine, Codeine Phosphate, Dihydrocodeine, Ethylmorphine, Vicodin, Lorcet, Dilaudid, Hydrostat, Koalin and Morphine mixture, Pholcodine, Dextromethophan, Quetiapine, Quinolone Antibiotics, Benadryl, Tylenol PM, Advil PM, and other medications contain diphenhydramineFentanyl, Hydrocodone, Hydromorphone, Meperidine, Methadone Oxycodone
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Amphetamines (AMP)False PositiveFalse Negative
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Amantadine, brompheniramine, bupropion, chlorpromazine, clomipramine, dextromethorphan, diphenhydramine, doxylamine, naproxen, promethazine, quetiapine, quinolones (ofloxacin and gatifloxacin), ranitidine, sertraline, thioridazine, trazodone, venlafaxine, verapamil, Dexamphetamine Sulphate, pseudoephedrine, phentermine, Beta blockers like labetalol (Trandate)
Diet pills like phentermine (Adipex-P), Medication to treat nausea and vomiting like phenothiazines (Promethazine)
Over-the-counter cold, sinus and nasal decongestants like ephedrine and pseudoephedrine (Sudafed) and Vicks inhaler, Bananas		MDMA (ecstasy)Synthetic amphetamines (cathinones, bath salts, etc)
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Benzodiazepines (BZO)False PositiveFalse Negative
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Sertraline, Oxaprozin, Efavirenz, naproxen and oxaprozin, Alprazolam ( Xanax), Bromazepam, Tranxene, Librium, Frisium, Briantum, Diazepam, ProSom, Rohypnol, Paxipam, Pacinone, Lorazepam, Noctamide, Nitrazepam, Serax, RestorilClonazepam, Alprazolam, Lorazepam
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Cannabinoids (THC)False PositiveFalse Negative
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Naproxen, Ibuprofen, Efavirenz, Baby washes, Hemp food products, CBD Oil
HIV medication like efavirenz (Sustiva)
Proton-pump inhibitors, specifically pantoprazole (Protonix)
Some vitamin B supplements that come from hemp seed oil, Antihistamines, Prevacid, promethazine, riboflavin, ethacrynic acid,		Synthetic cannabinoids
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Phencyclidine (PCP)False PositiveFalse Negative
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Dextromethorphan, , Ketamine, Tramadol, Venlafaxine, Naproxen, Ibuprofen, NyQuil, Benadryl imipramine, meperidine, doxylamine, lamotrigine, clonazepam, Benadryl, Tylenol PM, Advil PM, and other medications contain diphenhydramine, SNRIs, such as Effexor XR or Pristiq
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Tricyclic Antidepressants (TCA)False PositiveFalse Negative
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Carbamazepine, Cyclobenzaprine, Diphenhydramine, Phenothiazines, dextromethorphan, meperidine, doxylamine, ketamine, lamotrigine, tramadol, venlafaxine and desvenlafaxine, Amitriptyline, Flexeril, Periactin, Prothiaden, Sinequan, Xepin, Gamanil, Lomont, Promethazine, certain antipsychotic medications, antihistamines
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Methamphetamines (MET)False PositiveFalse Negative
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Decongestants, Ritalin (methylphenidate),Adderall, Quinolone antibiotics like Levofloxacin or Ofloxacin, or Metformin, Desoxyn, Methedrine, Methamprex, Vick's Inhaler, OTC Nasal Inhaler pseudoephedrine, promethazine, Trazodone, Buprion, brompheniramine,chlorpromazine, clomipramine, dextromethorphan, diphenhydramine, doxylamine, ibuprofen, naproxen, quetiapine, quinolones (ofloxacin and gatifloxacin), ranitidine, sertraline, thioridazine, venlafaxine, verapamil.
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Cocaine (COC)False PositiveFalse Negative
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Coca tea, lidocaine, fluconazole, zolpidem
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Methadone (MTD)False PositiveFalse Negative
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Benadryl, verpamil, quetiapine,Benadryl, Medinex, Nytol, Panadol Night, NyQuil, Dolophine, Physetone, Benadryl, Tylenol PM, Advil PM, and other medications contain diphenhydramine, Doxylamine, Clomipramine, Chlorpromazine, Quetiapine, Thioridazine
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Oxycodone (OXY)False PositiveFalse Negative
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Vicodin, Lorcet, Dilaudid, Hydrostat
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Buprenorphine (BUP)False PositiveFalse Negative
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morphine, methadone, codeine, and dihydrocodeine
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MDMA (Ecstasy)False PositiveFalse Negative
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Love Drug (MDA), trazodone, metoprolol and the fenofibrate metabolite, fenofibric acid, bupropion, and antipsychotic drugs such as promethazine and chlorpromazine.
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Barbiturates (BAR)False PositiveFalse Negative
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Ibuprofen, Naproxen, Allobarbital, Alphenol, Amobarbital, Aprobarbital, Butethal, Butalbital, Butisol, Soneryl, Nembutal, Donnatal, Luminal, Phenytoin, Secondal, NSAIDs, Pain medication like ibuprofen (Advil/Motrin) and naproxen sodium (Aleve)
Sleep aids like doxylamine (Unisom)
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Tramadol (TRA)False PositiveFalse Negative
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Venlafixine, exofenadine hydrochloride for treatment of skin allergy
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Ketamine (KET)False PositiveFalse Negative
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quetiapine, Promethazine
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Kratom (KRA)False PositiveFalse Negative
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Methadone Metabolite (EDDP)
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Cotinine (COT)False PositiveFalse Negative
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Nicotine
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Propoxyphene (PPX)False PositiveFalse Negative
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methadone, cyclobenzaprine (Flexeril), doxylamine (Ny-Quil), diphenhydramine
(Benadryl), imipramine
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PSY-PsilocybinFalse PositivesFalse Negatives
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Tylenol and Nortriptyline
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