GC/MS Drug Test? What is it?

[rybomaster]

What is a GC/MS drug test? Is that hair, blood, or urine? If I did coke 3 weeks ago would that show up in a GC/MS test? Is there anything I can do to prevent it from showing up?

[djscotphreak]

GC/MS is done by way of urine. It is a very accurate method of drug testing and is considered to be the "gold standard" in the drug testing industry. Drugs screened are.

thc (marijuana)

cocaine (crack)

opiates/morphine (heroin)

amphetamines (speed)

methamphetamines/mdma (ecstasy)

pcp (angel dust)

barbiturates (downers)

benzodiazepines (valium)

cotinine (tobacco)

With exception of THC...you are safe as long as you give yourself at least 72 hours...96 hours is almost guaranteed clean. Coke is usually out at max...72 hrs

Good Luck!

[knightcrawler]

GC/MS is an abbreviation for gas chromatography/mass spectrometry. this is a combined method of modern chemical analysis in which a test sample, in this case being a drug test sample, whether it be from urine, blood, or hair, is separated into individual chemical components (the traces of drugs) through GC. once the components in question are found and separated, they can be quantified through MS, after which the resulting value is compared to a standard pass/fail value.

GC/MS is regarded as the most precise method of drug testing, and as said before, can be performed on either urine, blood or hair. as previously posted, urine is clean after about 72 hrs. i believe blood will take longer; maybe a month. and hair samples can contain residue for several months.

however, most workplaces usually only test in urine samples, due to the high cost of GC/MS testing. usually, if a first urine sample comes out with questionable results, they may request a blood sample afterwards. but in your case, three weeks will have cleaned out your piss already. generally the only workplaces which request blood and/or hair samples are government or pharmaceutical jobs.

:book:

[djscotphreak]

After that scientific explanation which was very elaborate...you use the word "piss" in the last paragraph struck me kinda funny...very informative though! :laugh:

[robbkbump]

Actually, GC/MS testing in medicine is generally done on *blood samples* -- including drug screening. Although pre-employment screens in certain employment areas use GC/MS on urine samples -- *post-employment* in some our done on blood as a part of the employment contract and where regulated by law.

Because blood testing is an invasive procedure defined by law, it can usually only be done by court order, with some exceptions. Regulated employment classes -- the military, certain law enforcement jobs, certain transportation jobs, and certain pharmaceutical jobs and medical jobs can use blood tests *after* employment. However, cause is usually necessary.

Even then, though, other methods are usually done before GC/MS, as disco mentioned, because of the huge cost (from $800 and up a sample, depending on the tests).

And, for blood, actually, GC/MS tests can find virtually *any* substance one is looking for, assuming it has a chemical profile.

Keep in mind, however, there are substances which simply aren't around in any quantity to measure: LSD, for instance.

But blood GC/MS tests done for drug-enforcement work, intelligence agencies, etc., for instance, cover some 100 substances, metabolites, and classes, even odd chemical agents. Again, rare, but these are done.

In general, urine tests (non GC/MS) often list LSD and some now even Ketamine -- but neither are actually being tested for by any commonly known testing method (or are detectable with regular testing methods).

However, Dextromethorphan *can* and *has* caused false-positives for PCP in some pre-employment urine tests, and some home blood test kits, as well as ER toxicology screens (these are documented). In the past three years, over a dozen have been detected and resolved with further testing. Contrary to popular belief, DXM does not cause false opiate/opiod positive's -- at least none documented in peer literature (even when two studies were done specifically to find if this were possible).

-- Rob

[oak]

Not sure Bro. Good Luck to ya

[djscotphreak]

What do you mean non-urine test list LSD?

Are you saying the company who is doing the drug test/mfg the drug test kit company says the test itself can pick up LSD?

That is news to me...I myself am not really sure on the entire "LSD testing" myself...could you elaborate just a little tiny bit on that one

[knightcrawler]

Originally posted by djscotphreak

After that scientific explanation which was very elaborate...you use the word "piss" in the last paragraph struck me kinda funny...very informative though!

yeah, writing that one put a stretch on the brain (quite common these days), so i had to let loose at the end!

[rybomaster]

Thanks so much for the info guys! I really appreciate it!

[robbkbump]

Sure...

There are many companies that do drug screening, both urine and blood, which use standard methods (reagent testing), which includes that for LSD (and/or its metabolites).

Because LSD is ingested in such miniscule amounts (several hundred micrograms at best, often only a few), and it is metabolized within an hour, no known reagent test in the blood or urine can detect it after a few hours in blood or urine after more than 12 hours directly. There *are* blood tests which can detect metabolites, but these are rarely used, and generally in research or medical fields -- not in employment screening. Again, GC/MS results can detect LSD metabolites within some hours afterwards in blood, and conceivably in certain central nervous system fluids (not spinal fliud, contrary to popular belief) -- but this isn't legal in a drug screen.

Generally speaking, the detection of LSD and it's metabolites is so difficult for drug testing purposes it is not attempted as a general method except in rare research or the most senstitive positions (intelligence, military, etc.). It takes a very good chemist, good lab techs, and usually both computer and hands-on review of results to determine results, even today.

However, several companies continue to advertise in pre-employment urine screens that "LSD" is included in their screening process on their paperwork. This isn't illegal, by the way. It's not false advertising. They do use a basic reagent, it just isn't *precise* (vs. accurate) enough to detect LSD or it's metabolites to do the job in urine.

Theoretically, if one had dosed a large amount of LSD within an hour or two, and took the test, it is possible to get a positive reading, as enough metabolite could react with a very precise urine reagent.

LSD is a unique case, given it's extremely miniscule dosing, and it's unique process of being metabolized by the body so quickly, and by so many parallel means and so completely. There are few other substances which compare (drugs or chemicals, except for exotic poisons and chemical weapons).

-- Rob