How Long Does Weed Stay in the System? A South African Take

red blood cells with marijuana leaves in them

Image provided by pxfuel

We have all heard so many conflicting debates about weed and its safety across the board. This includes topics like how it affects brain development to how it impacts people’s day-to-day ability to function.


Hell, with how information is distributed nowadays, some of us are still confused. Is weed legal here in good old South Africa? It is, but for personal use only.


With that out the way, we would like to focus on the other nitty-gritty aspects of weed. Questions we seek to answer are ones like, is weed safe? How long will it take to feel the effects? How long it takes for the effects to wear off? How is weed tested for? And most importantly, how long does weed stay in your system?


a scientist looking into a microscope.

Image provided by pxfuel

Some Science About Weed

Let’s start off by tackling the safety of cannabis and all the stigma that surrounds the use of it. The short answer here is that using any form of THC (tetrahydrocannabinol) and CBD (cannabidiol) is fairly safe. You can even give your dog CBD!


Do you have a friend, colleague, or relative that says things like the following to you? “Don’t you know that stuff will rot your brain?” Now, you can kindly refer them to all the new studies that have been done to disprove this.


Yes, it is true that dagga can have a negative effect on a growing brain, but one that is already fully developed will not suffer any long-term effects. That is according to this study done by the National Institutes of Health’s sub-division, the National Institute on Drug Abuse.


In other words, not some random person on TikTok or Facebook.


A woman touching noses with her dog.

Image provided by pxfuel

How Long Does It Take To Feel the Effects of Weed?

Now with all the boring stuff out of the way, let’s dive into the fun side of things. Before you can know how long dagga stays in your system, you need to know how long it takes to get into your system.


According to a study done by Northwestern University, when smoking, vaping, or dabbing, the effects can be felt almost instantly. However, if you have chosen to ingest the cannabis product of your choice, then it can take a rather long time as it is up to how your body digests food.


A woman blowing lots of smoke

Image provided by pxfuel

How Long Does the Effects of Weed Last?

Very similar to how you choose to take the cannabis product dictates how long it takes before you feel the effects. It also dictates how intense the effects are and how long they last.


When smoking or vaping dagga, you will hit the zenith of experience within around 10 minutes. These effects can last anywhere between one to three hours. Although according to the previously mentioned Northwestern University study, some reported the effects lasting as long as eight hours.


When using edibles, the effects usually peak after around two hours and can last up to a whopping 24 hours. However, if you were to use the dabbing method, you get a mixture of these results.


The effects reach their peak within a couple of minutes and can last the entire day. This is due to the high concentration of THC, so tread carefully with this method.


A drop of blood being tested.

Image provided by pxfuel

How Do They Test for Weed?

So, you’re ready to get your first CBD oil and quotations, but want to know how you use cannabis oil, and how do they even test for dagga? These are all valid and natural questions. Let’s start with how they test for dagga.


Labs such as Lancet Laboratory and Ampath are usually the go-to testing labs in South Africa. As suggested by Labour Guide, these labs use blood, hair, and urine to test for all sorts of drugs, including cannabis. However, some labs can also test with saliva.

What Is the Purpose of TheseTests?

There are many reasons to take cannabis products, from anxiety to sleep deprivation and even to help with muscle recovery. Yet, why would someone want to test for weed, especially if it is legal for personal use?


Below you will find five reasons why you might be tested for Mary Jane, according to


a woman is handing a joint to you.

Image provided by pxfuel


  • Legal and forensic testing is one the most common reasons you might be tested for dagga. This is because it could be evidence for an ongoing trial or legal case such as a child endangerment case.
  • Another reason you may be tested for marijuana is if you want to join the military. In that case, military testing will be used to determine if you are fit for duty.
  • For any aspiring athletes out there, it is worth noting that all levels of athletes are subject to athletic testing.
  • Despite the personal use of cannabis products being legal, some employers still have the right to impose employment testing. This is because some jobs require the operation of heavy machinery or team members’ lives to be in one another’s hands, and intoxication of any kind would be unacceptable.
  • On rare occasions, it might be necessary to undergo medical screening for the use of any cannabis products, as it may have an adverse effect on a particular medication you may need to start taking.

What Does the Test Measure?

What exactly are the labs looking for when you submit your hair, blood, saliva, or urine for a test? According to, there are over 100 cannabinoids that are produced while your body is breaking down a cannabis product.


However, the main cannabinoid that is tested for is delta-9-THC. Very rarely will they include other cannabinoids, such as CBD.


CBD oil next to a marijuana plant.

Image provided by pxfuel

How Long Before You Can Expect Results?

Test results can be made available anywhere within a few hours to a couple of business days. It all depends on the type of test done and the quality of the sample.


It is also worth remembering that these tests are to discover the use of cannabis products, not whether someone is currently under the influence of any substances.

How Long Does Weed Stay in Your Body?

Enough information let’s finally answer, how long does it take for weed to get out of your system? The answer is very dependent on what part of the system is being tested. To make it as easy for you to understand, we have broken them into their individual parts.

How Long Does Weed Stay in Blood?

A blood test for any Mary Jane-related products will only test positive within the first seven days after you have partaken in the devil’s lettuce, gummies, or oils. In some cases, the cannabinoids deteriorate within hours of use, which is why blood is not a popular testing option.


A marijuana forest.

Image provided by pxfuel

How Long Does Weed Stay in Hair?

Hair clings to cannabinoids as if its life depends on them. Hair has a testing sample estimated detection window of up to 90 days. That’s up to a staggering three months after you have taken any cannabis-related products.

How Long Does Weed Stay in Saliva?

Saliva is the exact opposite of hair, where it will only retain any evidence of a Mary Jane visit for up to 24 hours.

How Long Does Weed Stay in Urine?

So, how long does weed stay in your system for a urine test? Well, urine is actually the second-longest clinger to any evidence that you have puff-puff-passed. It will remain in your urine for up to six weeks for heavy users.

How Long Does Weed Stay in Your System if You Smoked Once?

You may have noticed we only used heavy users in the “how long does dagga stay in your urine?” section above. That is because for first-timers or light cannabis users, your urine will actually only hold cannabinoids for up to three days.


Other testing methods have a smaller window of change whether you used marijuana once or 300 times. That is not to say it doesn’t affect the amount of time weed stays in your system. It does, just not on as large of a scale as urine.


a Marijuana plant.

Image provided by pxfuel

How To Test Negative for Weed?

There are many marijuana myths out in the world, some that are harmful and others more benign. One of the more harmless myths is that you can detox to beat the test. In fact, if you dare to search for a detoxification kit for marijuana, you will find many options to help you “beat the test.”


Yet, with the limited research available, the only clear thing is that these kits do not seem to substantiate the claims offered in their marketing. If you are looking to get clean, you will have to do it the natural way.


If you are really struggling with getting clean, you can always reach out to some amazing resources that will help you achieve your goals. Now that we have answered, how long does weed take to get out of your system? Use the information responsibly and help spread the word so that you and your fellow CBD and THC enthusiasts can live healthily.



National Institutes of Health Webpage –


Northwestern University Webpage –


Labour Guide Web Page –

Flying high – Weed in the workplace Web Page –

Marijuana (THC) Testing


Narcotics Anonymous South Africa Web Page –

Contact Narcotics Anonymous


We will be happy to hear your thoughts

Leave a reply