i have never used cocaine but it showed up in a recent drug test
Drug Test - What will cause a false positive for Cocaine on a urine test?
Question posted by bikerbabe1 on 27 Sep 2010
Last updated on 3 August 2023
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6 Answers
KenInAMinor
10 May 2017
I'm a Licensed Clinical Therapist working at a drug and alcohol clinic in Hagerstown, MD. I spoke with a laboratory technician at Redwood labs regarding possible causes of false positives for cocaine. She said that information suggesting that antibiotics such as amoxicillin or ampicillin causing a false positive is 30 years old and out of date. According to Redwood Labs, there are no current over the counter or prescription medications that will cause a false positive for cocaine.
GinaPA
6 Jan 2018
Then I suggest you educate yourself on this at reliable, respectable medical websites rather than listening to ONE person--WHO WORKS AT A LAB!!!
KenInAMinor
6 Jan 2018
Implying that that was my only source. It's not just one person at one medical lab. The gold standard is peer reviewed research in trade journals and there is significant evidence to support the idea that the medications listed in this blog no longer cause false positives. There are substances that do, but none of them are legal in the United States and most of them are food products that are derived from the same plant.
GinaPA
7 Jan 2018
Then how would you explain all the others who have reported they tested false positive (including myself, which I would swear to on a Bible that I did not take what I was accused of)? And how would you explain the many other articles by medical experts who say differently?
Ken_M
28 April 2018
Gina your responses look just like a tweet from Trump
Samiam1978
12 May 2018
I know you are wrong. I tested positive for it last week and know for a fact I have not used any. It is exactly that kind of thinking which can ruin an innocent persons life.
SayNope2Dope
17 May 2018
Maybe that wasn't your only source, but it is the one you chose to give credit to what you say, which means it was your best source, and a lab tech isn't really a reliable source at all. When giving information to others such as this, people always state their most reliable source, and you chose a lab tech. That should suggest to most people that this information has minimal credibility attached to it. And I get that whatever research was reviewed by whoever makes you believe there is signigicant evidence to support the idea that medications on this blog no longer cause false positives, and you have the right to feel it is enough and will stand by it. But as significant as you may believe that research to be, it is completely false. Several people on this thread, including myself, have had firsthand false positives come up on drug screens. And we didn't get that out of research from trade journals. We got that from being confronted about the failed tests.
"Let's have a serious discussion about your drug problem" when I have never touched drugs in my life was the most insulting thing I have ever heard. My husband had to basically cause hell with the Hospital to get them to look into what was going on because he knew for a fact I would never touch any type of drugs.Turned out it was one of my medications I was taking that caused the false positive, at which point all the Hospital could do was apologize profusely for accusing be of being a drug user. You have the right to believe your lab tech friend over those of us that have recently experienced false positives. But for everyone else reading this thus far, if you ever get a call from a professional that a loved one (son/daughter, niece/nephew, mom/dad, best friend, etc... ) tested positive for an illegal substance but swears they never touched drugs and gave zero prior history with substance abuse, I'd advise that they are most likely telling the truth and to not immediately jump. down their throat about it. Instead you probably should request a retest as well as a list of all medications that have been known to cause a false positive for that drug at any point in history, even if it has now been discredited as being capable of causing false positives. I'll bet 95% of thirst people would have recently taken a medication on that list.
KenInAMinor
8 June 2018
You have compelling points and to be fair, I assume the people I work with are telling the truth when they say it's a false positive. I don't have the luxury of ignoring a positive test in most cases because the majority of the people I work with are legally mandated. My response: typically one positive test doesn't mean a negative consequence. Any disputed tests are redone (labs hold all positive tests for at least 90-days) so the original sample is retested. The client is also retested. The results given then show what metabolites are or are not present. There is a small percentage of tests that are "Idiosyncratic" false positives (less than 1%). Retesting reduces the odds of a false positive. I am also open to the possibility that there are substances that may cause a false positive that haven't been identified.
The fly in the ointment is that agencies that are reported to (typically parole and probation or the courts) have a very strict view on the subject. One test by itself means much less than consecutive tests from a clinical standpoint. I also never accuse anyone of lying although to be fair, "resistance" is part of addiction and sometimes even in the face of overwhelming evidence people can remain in denial. How to separate the people in denial from users/addicts who are denying is the rub. In a clinical setting, the unfortunate reality is that sometimes the decision is driven by the legal system and not the clinician.
CRNP6
11 July 2018
KenlnAMinor is correct in that their are a ton of studies for her/him to fall back on. Random web sites are not always accurate, please look at your sources.
Another thought, if you are doing legal drugs that will test positive find out who the MRO is for the company that is ordering the drug testing, send the MRO a picture of your prescription bottles. Problem solved!
I do this all the time
Blibbyw
1 March 2019
You really should speak to more then a lab tech. Reach out to several testing facilities
Judy Evans 2
22 March 2017
I was told that it will.
coloradopat
22 Oct 2016
In addition to the currently listed substances that can cause a false positive for cocaine, I would like to add that the prescription drug Nuvigil (armodafinil) caused a false positive for both cocaine, amphetamines and possibly PCP. I currently take Nuvigil, Suboxone, Valium, and cannabis. I was hospitalized for a ruptured appendix, when they did a toxicology test, it showed I tested positive for cocaine, amphetamines, methamphetamine, PCP, and many others (the others were explainable from my other medications such as opiates and benzos).
I already knew Nuvigil causes a false positive for amphetamines, but we were complexed as to why it showed cocaine and PCP. I honestly haven't used any of those drugs since I was a teenager, I am now 37. The hospital's inaccurate toxicology report tested me positive for cocaine, amphetamine, methamphetamine, PCP, heroin, THC, benzos, barbiturates, and TCA (everything on its list except for methadone and oxycodone). The doctors did not believe me and treated me as a drug addict seeking more drugs, I was guilty until proven innocent by having a more accurate drug test done by a lab that showed they were all false positives.
My prescribing doctor and I are still confused as to why their drug test showed those false positives when other more accurate drug tests did not and could differentiate between Nuvigil and amphetamines, Suboxone and heroin, etc.
Hope this helps someone out there using one of these medications and is confused as to why they're testing positive for cocaine or anything else.
Punkyb
7 Sep 2016
I want to know the answer
Jandelles
28 Sep 2010
False positives for cocaine:
Amoxicillin
Ampicillin
Antibiotics
Coca tea, Coca leaf, Coca flour, Coca oil (banned in the US)
Diabetes
Kidney disease
Tonic water
christineATU
27 Sep 2010
I copied this excerpt from an article I recently read.
"Laboratory slip-ups are to blame for many of the mistaken test results. But even perfect labs running perfect tests will also find many false positives.
False positives are caused by:
* Nasal decongestants such as Dristan, Neosynephren, V
icks Nasal Spray, and Sudafed, which cause false positives for amphetamines.
* Poppy seeds like those on a dinner roll, which cause false positives for opiates. Even the highest-quality test currently available, the GCMS test, still confuses poppy seeds with heroin.
* Pain relievers such as Advil, Nuprin, Midol, Trendar, or any medicine containing ibuprofen cause false positives for marijuana.
* Antibiotics such as amoxicillin or ampicillin cause false positives for cocaine.
The above list is only a beginning. Most substances which people have in their blood have never been tested to see if they cause false positives. Indeed, even some natural body enzymes cause false positives. According to research validated by the Congressional Office of Technology Assessment, melanin, the natural pigment which makes skin dark, can cause false positives for marijuana."
I would recommend you request to be re-tested.
IhearttheOcean
28 Sep 2010
Good info
crazyma527
21 Jan 2012
had a pee test, havent used cocaine for two weeks, it should be clean..right?
sweetcherrypie40
7 Dec 2016
They want me to pay $200 to retest me.
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