How to Pass a Drug Test for Weed

Sponsored Post Written by the Pharmacist & Creator of Green Gone

Drug Tests: Separating Fact from Myth

Types of Drug Tests for Cannabis

Even though cannabis is legal in more than half the US, drug screenings are still common.

In the US, roughly 80% of all drug tests are standard, 5-panel, urine drug tests and check for THC and cannabis metabolites (the byproducts produced when your body processes cannabinoids).  Less common tests include blood, saliva, or hair.

Urine tests are commonly used for pre-employment screening, random screenings, and as part of probation terms. Even medical marijuana patients are subject to these screenings. 

Among these tests, THC secondary to marijuana use is the most common cause of failure. This is due to THC’s long half-life and common usage.

What if I fail a drug test in a legal state?

It doesn’t matter if cannabis is legal in your state, employers may discriminate against users.

Unfortunately, under the current federal laws in the USA, THC and marijuana metabolites are tested, regardless of the legal status of cannabis in the state in question.


How to Avoid Failing a Drug Test

Educate Yourself

To avoid failing a test you must educate yourself about:

  • The testing process
  • Methods of testing
  • Detoxification methods.

The key to education is avoiding misinformation (and there’s a whole lot of it on the internet). We intend to aid you in this process as well as identifying products trying to scam you along the way.

Following the following tips and tricks can help you pass a drug test for weed. 

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Hair Testing

Regardless of what you have read or heard, there is no known, proven way to decrease the amount of time required to pass a hair test.

The only proven ways to pass a hair test are abstinence, keeping hair length short, and time (and lots of time is needed).

Plan on keeping your hair less than 2″ length and abstain but still plan on 2-3 months, conservatively.

Is there anything I can do to pass a hair test?

Many hair detox products claim to work.

They don’t. There is no product on the market that can help you pass a hair test. 

Why Don’t Detox Products Work for Hair Tests?

There is no physiological mechanism to remove metabolites from the hair itself.

You cannot simply wash it out. It is “in” the surface of the hair and not just “on” the hair.

Many companies would love to take your money though.

However, there are limitations to a hair test, because of these limitations infrequent recreational users still may pass. There are also many variations of lab protocol and testing methods.

Bodily Fluids Testing (Urine, Blood, Saliva)

This is the most common method of testing because of the ease of sample collection, proof of consumption, and cost.


Drug Test Myth: Synthetic Urine

Let’s debunk the myth that synthetic urine is safe or effective.

If you’re saying, “But hey, synthetic urine worked for my friend’s uncles’s cousin,” hear me out.

Yes, synthetic urine has worked in the past. However, we strongly recommend against synthetic urine for the following reasons:

  1. Using a synthetic urine may be a crime. In some states, like Indiana, submitting a fake sample is considered fraud and is far more serious than failing a drug test.
  2. Synthetic specimens can be flagged numerous ways. If for example the temperature is slightly out of range or something looks wrong to the testers. For example, several months ago a customer was caught using a synthetic because the sample didn’t “smell right” so the sample was flagged for higher scrutiny.
  3. Witnesses might watch you urinate. Some tests are witnessed and you may not know prior to the test, increasing the risks involved with this approach.
  4. A recent study released in the journal of toxicology in Nov of 2016, described a clearly elucidated method for separating synthetic urine samples from proven human urine samples. Test centers WILL be implementing these procedures, effectively making synthetic urine an outdated approach.
  5. ALL synthetics have non-biological additives which they can find if your test is flagged for higher scrutiny.

To Summarize Why You Should NOT Use Synthetic Urine

Don’t commit a crime and don’t plan on this approach working. Sure, it has worked for people who’ve smoked cannabis in the past, but those days are rapidly coming to an end.

As many as 2% of all urine samples in the US for pre-employment have been proven to be synthetic urine samples. This has become too great of a liability for employers and test centers as synthetic samples have been used to erase polysubstance abuse of other harder drugs: cocaine, crystal meth, opiates (heroin), and benzodiazepines like Xanax.

Even legal medical marijuana patients are subjected to drug tests. Here are some tips & tricks on how to pass a drug test for weed. Don't fail for THC.
Following these tips can help you pass a drug test for weed.

Why is it so hard to remove marijuana metabolites from your system?

Marijuana Kinetics

The are several reasons it’s difficult to remove marijuana from bodily fluids.

The major issues associated with removing cannabis from your system scientifically speaking are:

  1. High lipophilicity of the metabolites (They’re fat soluble and have a long half-life)
  2. High protein binding of THC metabolites, and similar derivatives, in the bloodstream to albumin (only effectively eliminate free drug through the kidney and bowel).
  3. Bottleneck of metabolite formation in the liver (Your body can still generate metabolites several days after your final consumption event)

How Long Does Marijuana Stay In Your System?

The half-life of cannabis varies a great deal. How long it takes to excrete it depends on numerous factors such as the frequency of usage and the physiological attributes of the person in question (age, gender, size etc).

Generally, in order to test negative for a drug test, a cannabis user needs to stop consuming marijuana for a period of time so that the body can completely eliminate it.

  • A one time user typically takes 3-7 days to test negative.
  • An infrequent user might take between 7-10 days.
  • Daily users can take several weeks to well over a month or more.

It should also be noted that there are also reports of 1-2% of the population being “slow metabolizers” that either don’t possess the necessary liver enzymes or their output is dramatically reduced. This means it can take the body much longer to naturally excrete marijuana metabolites.

See also, how long does a weed hight last?

Even legal medical marijuana patients are subjected to drug tests. Here are some tips & tricks on how to pass a drug test for weed. Don't fail for THC.

What can you do to pass a drug test for weed?

Dilution of Urine

Some try to pass a urine test by diluting their urine or drinking a great deal of water. However, dilution has many limitations.

If you over-dilute your urine the site won’t accept the sample, as it won’t meet creatinine and specific gravity requirements for validity.

!! Note: Do not take large doses of oral creatinine to try to fool the urine test. Large doses of creatinine are required and it can irreversibly damage your kidneys. Besides the serious health risk, the test center will detect diluted urine with a high creatinine discrepancy.

However, light dilution of urine sample makes sense if you are already fairly close to passing.

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Hydration is key prior to your test and for the test itself. Most of the detox products online have some sort of diuretic, albeit reasonably so. Some of them are composed exclusively of several mixed diuretics.

Unfortunately, there’s no such thing as “magic” in the world of pharmacokinetics, and this doesn’t address the issue fully.


Increasing fiber may help to clear more drug through the bowel. There are several detox products available that are pretty much expensive fiber supplements.

Then right before your test, you do a process similar to the Certo Jell-O pectin method. This is where you take a large dose of dietary fiber a specific amount of time before your test.

The theory alleges this will help pull metabolites from biliary tract retention to your bowel and can help excrete more cannabinoids.

The problem with this approach is it is unnecessarily expensive, it only harnesses one mechanism, and it’s time-sensitive with highly complex instructions. So, if you fail, they claim it’s pretty much your own fault for not executing the method properly.

We put this to the test many times and could never get it to work reliably, or really at all.

The following products are fraudulent:

1. Products that claim to also cleanse nicotine, metals, or other drugs. These chemicals are completely different from THC metabolites. You cannot use one product to target numerous chemically dissimilar compounds. (In fact, it sounds more like you are using one product and targeting none.)
2. We’ve seen a product marketed online, the components are not explained well by the company. We suspect it’s a mix of homeopathic diuretics. It costs nothing to make, the price is $50, and it does not work.
3. There are even cheaper detox products. You can pay only $20 for a completely ineffective product. These are basically a blend of another diuretic, but some also contain milk thistle.

Don’t buy products that contain milk thistle.

Milk thistle is used as a liver detoxicant, however, it inhibits the actions of some liver enzymes like 3A4 and 2C9. These are the liver enzymes known to break down cannabis metabolites.

In fact, if you check THC aginst milk thistle in a proper drug interaction database, like Lexi Comp, it will result in a category C interaction. Milk Thistle can increase levels of THC in the body and decrease metabolism.

It doesn’t happen often, but cannabis CAN interact with some medications or herbs.

Taking a product with milk thistle can increase the amount of time to get a negative test. Don’t take a step in the wrong direction. Read your ingredient labels.


Miscellaneous Detox Drinks

Cannabis detox drinks won’t permanently cleanse but may work if you are already close to passing and need to dilute your sample a bit with a diuretic.

Again, this method is expensive considering you could get the same diuretic effect with tea, coffee, an energy drink, and water and save $30-$50.

Niacin does not impact urine tests. Niacin only makes the color of your sample more yellow, which allegedly “fools” the test centers.

However, all samples are also quantitatively tested for Scr and specific gravity. So it may look more like urine having a tint of yellow to it, but if the Scr and SG is low, it will be flagged for higher scrutiny. The dilutional aspect is really the only effective component.

Learn To Make Cannabis Capsules

The Best Ways to Pass a Urine Test for Weed

Lifestyle Modifications Can Help

There are lifestyle modifications that can help decrease the time it takes for the body to excrete cannabis. Some are only anecdotally supported, other modifications have more data supporting them.

  1. Total abstinence, including avoiding second-hand consumption (best evidence).
  2. Increase your dietary fiber intake (strong evidence).
  3. Eating a low carb diet initially, or calorie restrictions to loosen up metabolites (anecdotal).
  4. Cardio exercise (anecdotal).
  5. Staying adequately hydrated (strong evidence).

Still, these lifestyle modifications are often not enough. It could still take a regular user several weeks to detox completely.

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When Lifestyle Modifications Are Not Enough

If you are concerned about a potential drug screen and cannot wait that long, you need a detox product that actually works.

The perfect detox product would:

  • Provide reliable, repeatable results.
  • Not have time-sensitive directions.
  • Be permanent.
  • Not have complex instructions.
  • Hit THC and like metabolites from multiple targeted mechanisms.


A Product Designed By Pharmacists

There is only one product out there that does all this, designed after 2 years of trial and error: Green Gone. Like all products, Green Gone does have some limitations, but if you want a permanent cleanse it will do the job.

See Green Gone here:


Green Gone contains:

  • St John Wort – A proven potent liver enzyme inducer. Especially to enzyme pathway CYP3A4 and CYP2C9, the ones that generate THC metabolites. Some studies have shown St. John wort to more than double liver metabolism rate.
  • Sodium bicarb – This ingredient is surprisingly lacking in available products but the mechanism makes sense. The idea here is that the acidic THC metabolites generated have limited urine solubility, and therefore stay in your system longer. By modifying urine pH and increasing it you can increase the solubility of metabolites into the urine. This process has already been demonstrated with a variety of other drugs as well. Furthermore, this will synergistically help the diuretic be more effective because now it’s not just making urine more the urine being made will have more metabolites in it to flush.
  • White willow 15% extract – If you refer back to the beginning of this article we discussed the problems with THC metabolites and why they stay in your system so long. One of the major issues is protein binding. White willow contains salicyclates that bind to albumin and displace THC from the binding sites and help eliminate the free drug faster.
  • A mild diuretic and fiber source.


Green Gone is surprisingly affordable (maybe because it’s so new). It’s especially affordable compared to many other, less effective, marijuana detox products. Green Gone comes with a money back guarantee and the five-star reviews are piling up.

This product was created to help people. Marijuana detox is complicated, but it doesn’t have to be, Green Gone can help.


About the Author: Written by the pharmacist and creator of Green Gone. Email at or visit Green Gone LLC.

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