How long does Cannabis stay in your system?

How long does Cannabis stay in your system?

Australia's guide to marijuana and its effects on your body for drug tests or health (blood, urine, hair etc.). Find out how long weed stays in your system!

Cannabis legalisation is popping up around the world for medical and recreational use, and it’s creating a lot of positive changes. But it’s also leaving many people wondering how the popular and controversial plant’s many compounds affect the human body, how long it stays in users’ systems, and how to test for different levels of consumption.

Cannabis And Your Body

The effects of marijuana vary by the person, the cultivar or strain, and the method of delivery.

Variances By Person

Like all drugs, you must consider many other factors, including body weight, previous use, and if you’re using any other medications or alcohol with it, both of which will enhance your body’s reaction.

Marijuana Strains

Marijuana strains
Marijuana strains

Most regular cannabis users will tell you there are dozens of varieties of marijuana. Often referred to as strains, they relate to the plant’s chemistry. Each plant is made of different percentages of more than 545 chemical compounds.

This includes 140 terpenes, alkanes, nitrogenous compounds, sugars, fatty acids, non-cannabinoid phenols, phenylpropanoids, steroids, and more than 20 known flavonoids.

Every combination of cannabinoids, terpenes, flavonoids has a different effect on the user, and there are dozens of known strains. Some of the most popular include,


  • Sour Diesel contains about 19% THC, and most users report happy, uplifting feelings and find it helps reduce stress and anxiety.
  • Jack Herer has up to 24% THC and produces an energetic high that can reduce pain and anxiety.
  • Strawberry Cough contains between 22% and 26% THC, and reviews show it provides a cerebral, energising high that alleviates stress, anxiety, and pain.


  • Northern Lights has about 17% to 20% THC, and users say it produces a powerful body high that boosts mood and creativity while offering strong pain relief and reducing nausea and promoting sleep.
  • Bubba Kush includes around 16.5% THC and is ideal for relaxation, improving sleep, and relieving stress.
  • Granddaddy Purple contains between 17% and 23% THC, and reviews show it produces a general calm and happiness, promotes healthy sleep, and helps relax the body. Hybrid
  • Girl Scout Cookies has a high THC count with most flowers containing up to 28%. Users report a cerebral high with intense feelings of euphoria, pain relief, and sleepiness. Gorilla Glue includes about 20% THC and reviewers overwhelmingly report an intense calm and an uplifting mood.
  • OG Kush is another strain with a high percentage of THC, containing about 24%. Reviews conclude it improves moods, increases creativity, and is commonly used to relieve pain, nausea, and improve appetite. Adie Wilson-Poe, a cannabis researcher at Washington University in St. Louis who studies the plant’s potential for pain management explains,”

“We need to understand which constellations of plant chemistry are best suited for which indications and which kinds of patients, and which form of the CB1 receptor you happen to carry, because there are lots of mutations in that gene . . . So, understanding these mechanisms is absolutely crucial for providing these patients with personalised medicine that alleviates their symptoms without producing unwanted side effects.”

Method Of Delivery

Taking medicinal cannabis oil
Taking medicinal cannabis oil

Another way that marijuana’s effects on the body vary is by how you use it. Unlike the different strains that have many common themes, the only means of consumption that are similar are smoking and vaporisation, and that’s only in appearance.

Smoking - is the fastest method with an onset of minutes that peaks after 30 to 60 minutes.

Vaporisation - has the same results as smoking without the dangers of smoke inhalation.

Edible – takes the longest to take effect and varies more from patient-to-patient than other types of consumption. The onset is 45 to 90 minutes, and the duration is four to six hours, depending on the dose.

Sublingual – is the second-fastest method of delivery when taken correctly.

Transdermal – onset and duration vary significantly by the type of patch. These absorb through the blood vessels and can last from three to four or more hours. Some work for 24 to 48 hours.

Topical – These work on the top layer of skin, joints, and muscles. They don’t interact with the bloodstream and have an onset of about 20 minutes, and the duration varies by product.

Additionally, you can take cannabis in vaginal and anal suppositories. This method of delivery is ideal for taking large doses of THC without the intoxicating effects.

THC And Your Body

THC cannabis extracts
THC cannabis extracts

The compounds in the cannabis plant affect everyone differently, and this makes it difficult to pinpoint what effects THC will have on one patient to the next.

According to Joseph Rosado, an International Cannabis Solutions medical consultant,

“Each of us has a unique metabolism that processes cannabis at a different rate . . . Even among people of the same gender and age, individual lifestyle choices—such as levels of exercise and eating habits—may affect the amount of time required to pass a drug test.”

Delta-9-tetrahydrocannabinol, better known as THC, has psychoactive properties that cause users to get “high.” Some people can take a small dose, such as 2.5 mg and get pain relief, and experience intense euphoria.

Users with several months or years of taking cannabis with a high percentage of THC may need much more. Averaging 20 to 25 mg daily to relieve symptoms and still won’t get the extreme anxiousness and paranoia some feel following a much smaller dose. These patients benefit from the strains with a high-THC ratio, such as the Girl Scout Cookies and Strawberry Cough.

Short Term Effects Of THC

The most common short-term effects of THC include,

  • Increased appetite
  • Sense of relaxation
  • Trouble focusing
  • Intense focus
  • Dizziness
  • Altered time perception
  • Sleepiness
  • Pain relief
  • Improved mood

Negative effects are also possible, such as,

  • Restlessness
  • Paranoia
  • Anxiety
  • Dry mouth
  • Red eyes
  • Rapid heart rate
  • Short-term memory loss
  • Confusion

All positive and negative effects have a short duration.

Long Term Effects Of THC

There are few long-term studies on the impact of marijuana and the psychoactive compound, THC. Researchers and medical professionals are aware that long-term cannabis smokers have an increase in risks for lung and breathing-related conditions, such as pneumonia, bronchitis, and lung cancer.

These issues are due to smoking cannabis and not the plant’s compounds. The 2016 study referenced concludes that the number of cannabis smokers also smoking tobacco increases complications with long-term research.

CBD And Your Body

CBD cannabis
CBD cannabis

Cannabidiol or CBD is one of the most known cannabinoids next to THC. Like THC, the effects on the body vary by person, dose, and method of use.

Short Term Effects Of CBD

The most common short-term effects of CBD include,

  • Drowsiness (in higher doses)
  • Relieve inflammation
  • Reduce seizures
  • Improve mobility
  • Ease anxiety
  • Enhance mood

There are some mild negative side effects of CBD, such as

  • Upset stomach
  • Increased aggression
  • Reduced alertness
  • Diarrhea

A recent study, “Cannabidiol in Anxiety and Sleep: A Large Case Series” in The Permanente Journal, found long-term use of 10mg to 400 mg per day was safe and didn’t create a “toxic” effect on patients.

There are few long-term studies of CBD. The use of cannabinoids are becoming more accepted by medical communities around the world. More research will be available as more patients begin and continue using CBD to replace medications with fewer side effects. Physicians will have a plethora of data about the short-and long-term effects of different CBD doses.

The Entourage Effect

The entourage effect is the theory that all the compounds in the cannabis plant work together to provide the best results. This could explain why patients using synthetic cannabinoids, like Marinol, a lab-created THC, doesn’t work as well for some as a whole plant medicine that contains more than 100 additional cannabinoids, including CBD. In high doses, the phytocannabinoid without psychoactive responses can reduce the effects of THC that some users find it hard to tolerate.

Researchers came a step further by showing the theory is accurate with Sativex, a legal, plant-based medication, which combines THC and CBD. Patients react better to Sativex than Marinol. The CBD reduces the anxiety and paranoia that some people experience with high doses of THC.

However, that doesn’t mean that THC and CBD isolates are less effective. Instead, these have their place in cannabinoid medicine. For example, the same article in Wired Magazine that discusses marijuana and the entourage effect highlights the positives of THC for treating glaucoma.

Indiana University researcher, Alex Straiker, explains the problems they’ve come across in cannabinoid studies with CBD and THC.

“We found that it works, and THC does a nice job . . . But it’s actually blocked by CBD. People often think, oh yeah, CBD and THC work together. But in terms of CB1 receptor signalling, they actually oppose each other, or at least CBD opposes THC.”

Cannabis Drug Tests

Drug tests
Drug tests

The numerous ways to use medical marijuana make it more difficult than alcohol and other tests for drug use. Users can smoke, vape, eat, drink, and absorb it through the membranes under their tongue (sublingual) and through the veins (transdermal.) Additionally, medicinal users can take cannabis suppositories and topical applications.

The only way to take cannabis without the high is topical. Unless you have a cut, it won’t absorb into the bloodstream and the minute amount won’t produce euphoria.

Methods of Detection

There are a few ways to detect drugs in the body. The most common are urine, hair, oral fluid, blood, and sweat.


A California company has developed a THC breathalyser. A study found the device can detect THC for two to three hours after inhalation. However, this method can’t determine levels of consumption or impairment.

Urine tests

For regular users (a few times a week), urine tests can tell if you’ve used marijuana for up to four weeks. However, it’s important to note some reports of urinalysis coming back positive after over 30 days in heavy users (people who consume cannabis daily). Additionally, THC will test positive in your urine for five hours following consumption.

Most screenings test for metabolites, which is a byproduct of THC or THC-COOH. It’s not psychoactive and stays in the body’s fat tissue. Metabolites occur for all methods of cannabis consumption. Research shows that THC-COOH levels are detectable longer for edibles.

According to a 2004 study, “Detection Times of Drugs of Abuse in Body Fluids,”

“After oral intake, the detection time in urine seems to be longer, eg, after intake of 2 brownies containing 2.8% THC, the metabolite could be detected by EMIT (cutoff 20 ng/mL) for 5.9 days.”

Testing for THC-COOH can vary for the same reasons the cannabinoid’s effect on the human body differ—Dosage and potency of the THC, route of administration, and how often the person uses it, their metabolic rate and body mass.


Hair testing is the most contested way of testing for cannabis use. The hair follicles store THC for up to 90 days and longer for some people, depending on their last haircut. The testing sample must be 1.5 inches long to complete the screening. The reason for concern is that hair contamination can happen in multiple locations and isn’t as reliable for detecting regular use as bodily fluids.

Blood tests

Blood tests are more intrusive than other methods. However, this is the most accurate for measuring levels of THC within hours of use. Detection is possible within seconds, but the concentration of THC begins to peak at seven to eight minutes in your plasma and hits the half-life mark around 30 minutes following smoking or vaping. All traces of THC leave the blood about five hours following the last puff. On the other hand, the metabolites stay in the blood for 20 to57 hours for occasional users and three to thirteen days for heavy users.

Oral fluid

An oral swab tests your saliva for the presence of THC, which can stay inside your mouth until it completely metabolises, which can be 24 to 72 hours, depending on the person. Again, oral tests only work for smoking and vaporisation.

These tests only screen for THC, which has the potential to be a problem for anyone who uses CBD that has traces of THC. Some testing services may allow a small amount of THC to account for second-hand exposure and the growing popularity of CBD products that don’t produce psychoactive effects.

In most cases, strictly CBD patients have little to worry about in terms of drug testing. Law enforcement officials are just beginning to use tools now that test the difference between hemp and cannabis flowers. Most CBD products are still derived from hemp plants.

Along with these devices already in use, dozens of companies are working with medical cannabis researchers and law enforcement officials to develop more accurate methods of detection.

Getting Marijuana out of Your System

THC is stored in your fat cells. The more fat on your body, the longer it can take to get out of your system. Some users swear that hydration and exercise can increase the rate of metabolisation and help remove it from your body faster. Unfortunately, there isn’t any quantitative research on this topic. However, exercising before a drug test can increase the concentration of THC in the system. It’s best to stop any forms of exercise for at least 24 hours before testing to avoid causing the THC in your fat cells to release faster and increase the concentration.

A 2013 study consisting of 14 daily cannabis users found that 35 minutes of exercise on a stationary bicycle resulted in a small but statistically relevant increase in plasma THC levels. The tests were performed with food and after fasting but found no difference between the situations. Researchers believe the results show that working out may increase THC levels by releasing older THC from fat storage. In conclusion, the study’s authors conclude, “These data suggest the interpretation of blood THC levels in roadside and workplace tests might be complicated by recent exercise.”

While there are many ways people claim help you have a clean drug test, only one way is 100% guaranteed—Don’t use cannabis for a few weeks for occasional users, 30 days for regular users, and 60 days or more for heavy users.

Despite the long history of cannabis use for medical and recreational purposes, researchers are still learning how the amazing plant affects everyone and how to detect different levels in the body. The more scientists learn and understand about medical cannabis and precision dosing will help patients get proper treatment and assist law enforcement with intoxication levels and safe vehicle operation.

Disclaimer: This topic may represent illegal activity in certain regions. We do not encourage illegal activity. We understand that readers in locations where cannabis has been legalised may read these articles.