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How Long Does Weed Stay In Your System?

Determining how long does weed stays in your system is a scorching topic. Nevertheless, abstaining from marijuana is the only foolproof way to pass a pot drug test. But first, let’s look at the various reasons people get a test for cannabis.

  1. Legal issues
  2. Employment
  3. People using legal medical marijuana
  4. Accidents
  5. A family member or school suspects heavy use
  6. Forensics
  7. Sports activities

The active ingredient in marijuana is tetrahydrocannabinol (THC), as the liver breaks it down into a metabolite known as THC-COOH. Some tests check for this metabolization by-product rather than just THC. However, it is often the chemical many tests detect.

  • The primary factor in testing is the frequency of use.

The primary psychoactive chemical in pot, THC, is lipophilic, meaning it goes up into fat cells and deposits in fat tissue, the spleen, lungs, and liver. Organs and fat tissue release cannabinoids into the bloodstream, where metabolization gradually occurs. Excretion is by the feces 30-50% and 10-16% excreted in the urine as metabolites.

Here are the primary variables for testing positive for cannabis:

  • Weight
  • How much marijuana was smoked
  • How often smoked
  • Potency or percentage of THC
  • Metabolism rate

As an added benefit, quitting will help avoid smoking weed’s adverse health-related side effects. These can include breathing problems, depression and addiction, and others. Pot is fat-soluble. Fat-soluble means marijuana (THC) accumulates in the body’s fat cells.

This marijuana urine detection chart shows test outcomes depending on the usage rate.

Here are the detection rates in urine according to the frequency of usage:

● First-time use is noticeable within 24 hours and for 5 to 8 days afterward.

● Occasional usage is detectable from 11 to 18 days.

● *Regular use is detectable from 30 to 45 days (regular use constitutes 2 to 3 times a week).

● Daily user is detectable for up to 90 days.

The half-life of marijuana is 28 hours and 56 hours for chronic users. So, half of the ingested marijuana is still present in the bloodstream after 28 hours.

How long marijuana remains detectable depends primarily on the type of test and the frequency of usage. Some of the most popular types of tests include:

● Urine

● Blood

● Hair

● Saliva

Testing for marijuana and other drugs has advanced since testing became widespread in the 1980s.

Types of specimens

● Blood, urine, tissue, oral fluid, sweat, or hair.

Cannabis contains more than 100 types of cannabinoids, mostly inactive forms, and because there are many different synthetic cannabinoids in the market, accurate lab testing is complex and interpretation even harder.

Typically, the first test is a screening test, and the second is a confirmation of positives. Mass spectrometry is the gold standard.

Urine Testing

One of the biggest myths today about passing a marijuana urine drug test is that passing may not be possible if someone has smoked one joint within 30 days. That is not true. The bottom line is that there are too many factors to predict if you will test positive reliably, but one joint should probably not test positive after 30 days. However, according to studies, THC can be detected in the blood for up to 25 days after smoking one joint.

Flushing the body by fasting and drinking water may not remove all the cannabinoid chemicals from tissues. Nor will consuming certain foods, herbs, or vitamin supplements, mainly if used recently and heavy.

● Only long-term abstinence guarantees a negative test outcome.

As American society eases the legal restrictions on the sale and consumption of marijuana, it’s critical to remember that potential employers do not necessarily change their drug policies to reflect state laws and can mandate testing initially or randomly.

● Many companies require a drug test before hiring new employees, while other businesses randomly test their staff depending on their field of specialty.

● Testing positive on a marijuana drug test might be grounds for termination.

Over 30 states have legalized or decriminalized recreational or medical marijuana use.

● Legalization makes marijuana testing an even bigger issue.

● Urine can contain high concentrations of THC. It also has a more extended detection period than other tests.

Key factors include;

● body type

● metabolism rate

● amount of marijuana used

● frequency of usage

● marijuana-natural or synthetic

● Mode of use: inhalation or ingestion

Information regarding cannabinoids, specifically THC, indicates the body, following inhalation of marijuana smoke, rapidly absorbs it.

Blood Tests

While they are a good indicator of recent use, blood tests for pot are administered less frequently due to the invasive nature of obtaining a sample and the involved expense.

● A regular marijuana user will have THC in their bloodstream for two to seven days, which means the urine will contain levels that coincide with the waning blood levels.

How much THC makes its way into the body and bloodstream depends on these variables:

How deeply the user inhales the pot smoke

How long do they hold it in their lungs

Whether you inhale or ingest it

Hair Testing

Hair significantly differs from human blood or saliva when used for drug testing because hair provides a much longer detection window.

Depending on hair strands’ pigment content and the THC content of marijuana regularly smoked, THC may remain detectable in hair for up to one year or longer. However, you cannot tell when the person smoked or ingested it. Hair follicles are more indicative of recent use.

However, hair tests for pot cannot determine when a user last smoked marijuana. THC concentrations and other chemicals in pigmented hair are ten times higher than concentrations found in non-pigmented hair.

● Hair follicles bind with THC for more extended periods, up to seven days after a single use.

However, studies have shown that testing hair for THC traces can cause false positives because of secondhand exposure to marijuana.


Law enforcement in many parts of the country has started administering saliva tests to drivers they believe might have been using marijuana.

● THC has a very short lifespan in saliva but will test positive within about an hour of ingestion and last about 12 hours.

Be aware that while the U.S. Department of Labor allows on-site saliva drug testing, saliva drug testing is not acceptable by the U.S. Food and Drug Administration or the Substance Abuse and Mental Health Administration for use with Federal Mandated Drug Testing (DOT). In addition, the reliability of the tests and how they correlate with impairment have not been quantified and standardized.

● Saliva tests can detect THC for up to 24 hours only after smoking one marijuana joint.

While there are products on the market claiming to cleanse your urine, there is no natural way. Flushing your system with fluids will dilute your urine but won’t necessarily remove the THC-COOH from your body. It merely takes time. However, dilute urine will have less THC than more concentrated urine, which benefits. Unfortunately, over-drinking can be dangerous and lead to water intoxication.

All of these numbers are unique to different individuals. Marijuana testing kits will likely improve soon due to the drug’s greater accessibility. Eventually, it will be harder to avoid testing positive for marijuana, especially for regular users.


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