What is a False Positive Urine Test and What Causes It?
You might have heard that there are some false positive urine tests. May be you are worried whether yours might turn out false. For starters, the issue is all about what these tests are and what causes such results. Well, we provide you with meaningful insights to resolve your uncertainty.
What is a False Positive Urine Test?
In sedate screening, a “false positive” implies that an example is dishonestly announced as positive regardless of whether it is really tranquilize free. … A medication test false positive (or a bogus positive medication test result) is a mistaken test outcome that says a patient or guinea pig has a lot of medication metabolites in the body.
You can imagine the disappoint and utter disillusionment you might get if you are genuinely drug free but the medic testing you tells you are full of opiates in your body. Yes, you’ll miss the opportunity you are looking for. But if you know some of the factors that might lead to such false results, you might as well be in a position to defend yourself and ask for a more elaborate test.
With that in mind it’s vital to look at some of the factors that may lead to false positives in urine tests.
What Causes False Positives in Urine Tests?
Medication test bogus positives may come from a few potential reasons, some of which are the accompanying:
Inaccurate testing techniques: At the point when a positive outcome emerges in introductory screening tests, corroborative tests, for example, the GC/MS technique ought to be directed so as to evacuate any probability of getting a bogus positive to nil.
Exceptionally low medication test cut-off level. On the off chance that the medication testing research center uses a base limit an incentive for tranquilize affirmation that is excessively low, guineas pigs who experienced accidental introduction to sedate segments may get a positive outcome. For instance, used smoke from weed may render the outcomes positive if the cut-off level is excessively low.
Cross-reactivity of mixes like medication parts: It is conceivable that different mixes like dynamic medication metabolites might be recognized, for example, poppy seeds inaccurately thought to be sedatives.
Then again, bogus negatives may result from the accompanying variables:
Test defilement. Weakening of a pee test with water may diminish the grouping of a particular medication metabolite. Be that as it may, present day testing strategies have just thought about this situation, and are utilizing extra testing systems to decide if the example has been altered.
High medication test cut-off level. Setting a high slice off level may prompt non-identification of tests that contain a huge centralization of a specific medication. Let’s explain this further.
What Drugs are tested?
Medications tests are regularly done on pee, yet different sorts of samples are additionally utilized, for example, hair, spit or blood. The most usually screened substances, and furthermore required by Federal working environment rules, incorporate these five classifications of medications:
- Amphetamines/methamphetamine
- Sedatives/Heroin
- Cocaine
- Phencyclidine (PCP)
- Maryjane/THC/Cannabinoids
Additional categories, as noted by SAMHSA, may include:
- Barbiturates
- Ethanol (alcohol)
- Designer drugs like Spice, Bath Salts, or Ecstasy (MDMA)
- Prescription opioids like oxycodone, hydrocodone, methadone
- Benzodiazepines, like alprazolam (Xanax) or diazepam (Valium)
Understanding how drug tests are done will help clarify why false positives occur.
How are Drug Tests Done?
When beginning screening drugs tests (called immunoassays) bring about positive outcomes, a second corroborative (Gas Chromatography Mass Spectrometry or GC-MS) test – which ought to consistently be done on positive outcomes – incredibly diminishes the opportunity of a bogus positive, nearly decreasing the hazard to zero.
3 GC-MS is a quite certain test to recognize separate mixes inside an example. In any case, GS-MS can likewise prompt a bogus negative if the GC-MS segment isn’t intended to distinguish every potential compound.
The underlying immunoassay permits speedy, huge scope screenings with insignificant expense. At the point when pee or different examples are gathered, they are part into two examples, and one bit ought to be put something aside for corroborative testing. For occurrences where an underlying medication screen restores a positive outcome, the GC-MS test is run on this extra spared bit to verify or refute results. GC-MS is considered the “best quality level” for tranquilize testing
Once in a while, a medication test may report the nearness of illegal or professionally prescribed medications in the immunoassay, despite the fact that the individual has not utilized these medications. It is significant that in the event that you are experiencing drug testing, that you give a total and exact history of every single doctor prescribed medication, over-the-counter (OTC) meds, and nutrient, dietary enhancement, and home grown items utilized before the hour of the example assortment.
The aftereffects of your medication testing ought to stay private and kept separate from the standard worker work document.
Bogus positive medication test results have been accounted for in various medication classes. A portion of the more typical classes incorporate cold and sensitivity items, torment prescriptions, and medications for diseases:
- Antihistamines
- Antidepressants
- Antipsychotics
- Anti-toxins
- Analgesics
- Some over-the-counter (OTC) drugs
- Decongestants
The outline underneath distinguishes normal substances answered to cause a bogus positive outcome dependent on the underlying immunoassay testing. Keep in mind, any positive medication test ought to consistently be affirmed with an auxiliary test, for example, GC-MS that recognizes and gives distinguishing proof and levels of a particular compound.
Substances that May Meddle with Drug Testing
The list below highlights some of the substances that might meddle with these tests.
- amantadine (Osmolex ER) amphetamines1
- amitriptyline (Elavil, brand ended in US) LSD (lysergic corrosive diethyamide)13
- benzphetamine (Regimex) amphetamines1
- brompheniramine (Dimetapp) amphetamines and methamphetamines4,8
- bupropion (Aplenzin, Forfivo XL, Wellbutrin XL, Zyban) amphetamines and methamphetamines8, LSD13
- carbamazepine (Carbatrol, Equetro, Tegretol) tricyclic antidepressants1
- chlorpromazine: amphetamines and methamphetamines8, methadone8
- clomipramine (Anafranil): methadone8
- coca leaf tea: cocaine1
- cocaine sedatives, topical: cocaine1
- cyclobenzaprine: (Fexmid, Amrix, Flexeril [brand ended in US])
- tricyclic antidepressants1
- cyproheptadine tricyclic antidepressants1
- dextromethorphan (Nyquil Robitussin, Triaminic, Delsym)
Among many other similar non-prohibited drugs and substances as highlighted below
Additional Info
Dextromethorphan (Tussin)
Over-the-counter hack and cold items, for example, the hack suppressant dextromethorphan have been accounted for to prompt a bogus positive outcome for (phencyclidine) PCP and perhaps sedatives. Dextromethorphan is artificially identified with levorphanol, an opiate pain relieving. The body processes codeine to morphine and the two substances might be found after testing. Corroborative testing can recognize the items.
Poppy Seeds
Poppy seeds, frequently found on bagels, rolls, and baked goods have for some time been utilized as a resistance against positive sedative test outcomes experienced on a pee tranquilize screen. It is realized that poppy seeds do contain sedatives – explicitly morphine and codeine; be that as it may, content changes extraordinarily relying on seed source and handling. Nourishment preparing may bring down the sedative levels in poppy seeds.
In a recent report distributed in the Journal of Analytical Toxicology,10 specialists decided sedative fixations in sedative free volunteers from 15 minutes to 20 hours after utilization of crude poppy seeds (15 grams) and arranged poppy seeds on a roll. Focuses, both 300 and 1,200 g/mL were assessed in pee tests. Oral liquid focus shorts are set at 30 g/ml.
Utilizing the 2,000 g/mL cutoff for pee testing, morphine was not recognized in pee from seeds on moves; crude poppy seed utilization brought about a distinguishable level in pee during the initial 6 hours after utilization. At 20 hours, no morphine was distinguished for rolls or crude seeds in pee testing.
With the 300 g/mL cutoff for pee testing, morphine was distinguished after moves in 50 percent of tests at 20 hours, and in 100 percent of crude poppy seeds following 20 hours. With oral liquid testing, morphine fell underneath the 30 g/mL identification limit with moves following 30 minutes and from crude seeds at 60 minutes.
Oral testing and the higher cutoff level of 2,000 g/mL may assist with diminishing the quantity of bogus positives because of poppy seed utilization. In any case, the general population commonly eats rolls or baked goods and would have no explanation or want to devour unpalatable crude poppy seeds where morphine levels are distinguished significantly following 20 hours at the 300 g/mL limit.10
Oral and pee sedate testing can regularly recognize sedatives up to 48 to 72 hours after use.
Government specialists who command drug testing for bureaucratic workers have raised the necessary morphine cutoff focus from 300 to 2,000 g/mL to diminish the quantity of sedative bogus positives because of poppy seed utilization. This level is present starting at 2019.
NSAIDs (ibuprofen, naproxen)
NSAIDs, for example, ibuprofen, have frequently been involved in causing bogus positives however most examples are revised with another screening procedure if this is of concern. NSAIDs are effectively accessible OTC in the US and are broadly utilized. In one report, creators reasoned that intense or incessant utilization of ibuprofen or interminable utilization of naproxen were not normally connected with bogus positives however they do suggest optional testing if necessary.
Efavirenz (Sustiva)
Efavirenz doesn’t tie to cannabinoid receptors. Be that as it may, as noted in the efavirenz (Sustiva) bundle embed, bogus positive tests for cannabinoids (THC) have been accounted for when the CEDIA DAU Multilevel THC test is utilized. Bogus positive outcomes with other cannabinoid measures have not been watched.
False positive tests for benzodiazepines have likewise been accounted for and are likely because of the 8-hydroxy-efavirenz major metabolite.11
Novocaine or Lidocaine
Procaine (brane name: Novocain) or lidocaine use as a resistance for cocaine misuse is certainly not a legitimate reason. On the off chance that benzoylecgonine, the primary metabolite of cocaine is recognized in a medication test, the subject can’t guarantee that the outcome is a bogus positive because of Novocain organization, or some other “- caine” sedate.
Benzoylecgonine is just found in nature as a metabolite of cocaine, and there would be no other substantial purpose behind its essence in a medication screen.2 As recently referenced, corroborative testing with GC-MS will distinguish singular medications or metabolites in an example, and nearly dispense with the opportunity for a bogus positive outcome.
Sertraline (Zoloft)
As per one report, portions of sertraline (Zoloft) surpassing 150 mg/day could prompt bogus positive benzodiazepine pee sedate screens. Nasky and colleagues12 looked into 522 positive outcomes for tranquilize screens for benzodiazepines while taking sertraline however negative with GC-MS. They saw 26 of 98 records as distinguished as bogus positives.
The package for sertraline currently cautions about this chance under the ‘Research center Tests’ segment. Corroborative tests, for example, gas chromatography/mass spectrometry, will assist with distinguishing sertraline from benzodiazepines while surveying a speculated bogus positive.
Passive weed smoke
The contention of inward breath of “uninvolved” pot smoke from being in a live with individuals smoking maryjane (cannabis) is definitely not a legitimate reason, as the cut-off fixations for lab examination (generally 50 g/mL) are set well over that which may happen from latent inward breath.
Bogus Negatives
While it is hard to mess with an example, endeavors have been made to modify tests, regularly pee. Variations from the norm in the pee screen may demonstrate that outcomes might be a bogus negative or that there was purposeful defilement of the example.
Adulterants
A low creatinine lab worth can show that a pee test was messed with – either the subject weakened their pee by devouring unreasonable water only before testing, or water was added to the pee test. Creatinine levels are regularly utilized related to explicit gravity to decide whether tests have been weakened.
To help maintain a strategic distance from this issue, the testing lab may shading the water in their can to keep the example from being weakened with can water. The temperature of pee is additionally estimated, to help forestall utilization of a subbed pee test got all things considered.
Those endeavoring to thwart the medication screen procedure may attempt to add certain chemicals to the pee test to influence dependability, yet this frequently changes the pH, which is additionally tried. The most well-known adulterants utilized incorporate certain oxidizing operators, for example, nitrites, glutaraldehyde, chromates and incandescent lamp like dye and iodine.
There have additionally been reports of individuals utilizing items, for example, Visine eye drops to contaminate pee tests to cause a bogus negative outcome for THC from weed. Fixings in Visine, for example, the additive benzalkonium chloride or the borate support may diminish the grouping of 9-carboxy-THC in the underlying pee immunoassay; nonetheless, upon corroborative testing with GC-MS this metabolite will at present be detected. There is the chance pH might be changed, too.
Testing for adulterants notwithstanding medications might be mentioned by the individual requiring the medication screen.
Final Thoughts
In case a positive test outcome is accounted for by a medication screening and the benefactor confesses to utilizing drugs, no further tests should be finished. Notwithstanding, if an outcome returns positive and you deny having utilized such drugs, a corroborative test is required, typically Gas Chromatography Mass Spectrometry (GC/MS).