Blood Drug Testing — The Most Accurate Type of Drug Screening

Blood Drug Testing

A blood drug test is the technical analysis of blood sample, usually extracted from a vein on the inside of the arm or the back of your palm with a needle, or through fingerstick, to detect the use of illicit drugs. Unlike urine test (aka urinalysis), blood test detects the presence of the parent drug and not its inactive metabolites. Metabolites are the products created when your body breaks down the drug through the process of metabolism.

Drugs Detectable in Blood Test and Detection Windows

Which drugs can be detected in blood?

The drugs that can be detected in blood are:

  • Amphetamines
  • Methamphetamine
  • Barbiturates
  • Benzodiazepines
  • Cannabis
  • Cocaine
  • Codeine
  • Cotinine
  • LSD
  • PCP

A blood test has very short detection window for almost all drugs, especially marijuana (Cannabis). It normally disappears from the bloodstream within six hours, but for heavy smokers may be detectable for up to 24 hours. This means that after-hours smokers don’t really have to worry about being tested positive.

  • Amphetamines: 10-14 hours
  • Methamphetamine: 24 hours
  • Barbiturates: 1-2 days
  • Benzodiazepines: 6 — 48 hours
  • Cannabis: 6-24 hours
  • Cocaine: 12-24 hours
  • Codeine: 6-12 hours
  • Cotinine (metabolite of nicotine): 12-48 hours
  • LSD: 0 — 3 hours
  • PCP: 12-24 hours
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Are blood drug tests accurate?

Yes, blood drug tests are accurate and virtually impossible to beat. Legally prescribed drugs can also be detected using this test. However, blood tests are not commonly used due to their invasiveness, cost, required equipment, and long waiting time to get results.

Blood Drug Test — Accurate but not Common

If administered during the detection window, blood testing is the most accurate approach for detecting drugs. Moreover, it’s the type of test that’s virtually impossible to beat, and if the donor takes any adulterants – no matter even if they are legal – they also might be detected in the blood.

However, it is not very common because of several reasons. Firstly, it’s the most invasive of all the drug tests. Secondly, it is one of the most, if not the most expensive blood test. What’s more, it requires medically trained administrators and specialized equipment, and yet the results can take up to a week, while several other tests such as saliva test or urinalysis can offer on the spot results.

When is a Blood Test Required?

Blood drug testing is required for people who are applying for insurance, for potential employees applying for jobs, and in some cases blood tests are required as part of a court order.

As mentioned earlier, a blood test is not very common and is only required when a lot of money or law is on the line. There are however certain cases where a blood drug test might be required. Insurance companies can require a blood drug test when a person applies for an insurance policy. An employer may require their potential employees for drug screen through a blood test before hiring. In rare cases, a blood test may also be required after a court’s order.

How to Pass a Blood Test

Since blood test has a short detection, it’s very easy to pass it. All you need to do it stop taking drugs if you’re expecting a blood test. However, since adulterants taken to beat drug tests are very easy to detect, using them can be counterproductive. Eating healthy foods, drinking plenty of water, and fresh juices, and doing exercise can help your body quickly metabolize the drugs into your blood, so you’ll be good as blood test only detects parent drug.

Blood Drug Testing — The Most Accurate Type of Drug Screening

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Comments 8

  • After smoking cannabis for 20+ yrs my employer have introduced blood tests. I have read the article but would like confirmation that the THC in my fat cells will not be detected. I have not smoked for 4 weeks now but i am exercising more trying to cleanse my body. Will the test pick up any trace from my fat cells releasing THC ?

  • MY SON HAD A BLOOD TEST DRAWN AND TESTED ON MAY 2. HE HAS BEEN TO COURT 4 TIMES ALREADY AND THEY SAY THEY ARE STILL WORKING ON IT.THEY SAID THEY ARE DOING A SPECIAL TEST FOR OPIATES. I AM A MED TECH AND I HAVE NEVER HEARD OF SUCH A THING AN OPIATE IS AN OPIATE. CAN YOU EXPLAIN THIS TO ME

  • Can i pass a blood test for cocaine if last used almost 36 hours prior? Also take note that it was a small amount and used intravenous

  • Can weed be detected in my blood or hair ,in any way if I have not smoke in 2 years ?

  • I got 2 days to pass a drug test wit blood what can I do

  • Can I pass a blood drug test taking blood samples with being on pain management and they said the want a blood test to test and I just smoked weed 2 days ago and I dont want to get in trouble .I smoke it to help me sleep and easy more pain with my pain pill too.

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