How Long Does Weed Stay in Your System?
Factors affecting how long weed stays in the body include frequency of use, genetics, other drug or medication use, body fat percentage and more.
Marijuana, sometimes referred to as weed, pot, dope, Mary Jane or cannabis, is the most commonly used federally illegal drug in the United States, with an estimated 48.2 million people using it in 2019. Marijuana refers to the dried flowers, leaves, stems and seeds of the cannabis plant and contains hundreds of compounds (often called cannabinoids). These compounds contain both tetrahydrocannabinol (THC), which is impairing or “mind-altering,” and cannabidiol (CBD), which is not impairing and does not cause a “high.”
Like many drugs, there are a variety of factors that can affect how long marijuana is detectable. How often a person uses marijuana, the THC content, body fat, genetics, how the drug test is measured (blood, urine, saliva, etc.) and many other factors can determine how long marijuana remains in a person’s system.
What Happens When You Consume Weed?
The effects of marijuana can vary from person to person — some feeling relaxed or euphoric, while others can feel anxious and paranoid. This can depend on a number of characteristics like genetics, body fat, THC content and how marijuana is ingested (smoking or eating). After smoking marijuana, THC rapidly enters the bloodstream, where it can make you feel “high.” If marijuana is ingested orally, usually as edibles, it takes longer to be absorbed into the blood and can range from about 20 minutes to an hour and a half.
Weed Side Effects
Short-term effects of consuming marijuana (memory, problem-solving, coordination and driving impairment) are more pronounced in the first hour or two but can last for up to 24 hours. Because there is so much variation between strains of marijuana, other effects can be varied.
Other effects can include:
- Dry mouth
- Swollen eyelids
- Increased appetite (“the munchies”)
- Distorted perception
- Loss of coordination
- Trouble with thinking, memory and problem solving
- Increased heart rate
How Is Weed Processed by the Body?
THC is a sticky, easily vaporized compound that readily dissolves into fats. Once in the body, it is deposited into fatty (adipose) tissue like the liver, lungs and spleen. THC is metabolized by the liver to 11-OH-THC and then further metabolized to an inactive compound (THCCOOH). There are two enzymes responsible for this metabolism, and there can be genetic variation in these — meaning some people may metabolize marijuana quickly and others will metabolize it slowly.
Factors Determining How Long Weed Stays in Your System
Many factors can affect the amount of time that marijuana remains in the body after consuming it. The effects of marijuana can be felt within minutes up to over an hour, depending on how it was consumed.
Other factors that can influence how long marijuana is detectable in the body include:
- Body fat percentage: Those with higher body fat percentages may have detectable levels of marijuana for a longer time.
- Genetics: Some people may be genetically predisposed to metabolizing marijuana more quickly or more slowly.
- Frequency of use: Infrequent users clear marijuana more quickly than frequent users.
- Other drugs or medications: The enzymes responsible for marijuana metabolism (CYP2C9 and CYP3A4) can be sped up or slowed down by other drugs or medications.
- Potency of marijuana
- Tolerance level
How Long Does It Take Weed to Leave Your System?
The half-life of a drug is the time it takes for the body to metabolize and eliminate half of the substance. While there are a variety of cannabinoids, THC is the one most drug tests look for. In the body, THC is broken down into metabolites, which are stored in body fat until finally being excreted through feces and urine.
Some marijuana metabolites have half-lives of 20 hours, but others can be as long as 10–13 days. It can ultimately take three to five half-lives for these metabolites to be completely eliminated. This means it can take between five and 65 days for marijuana to be completely eliminated, depending on factors like how often marijuana is consumed, body fat percentage, genetics and others.
How Long Does Weed Stay in Urine?
Urine tests can show recent marijuana use (not current intoxication) because of the delay between use and the body breaking THC down into metabolites. It can take an estimated one to four days for marijuana to be undetectable in urine, though some studies have shown detectable levels for up to 70 days with chronic use.
How Long Does Weed Stay in Your Blood?
Because marijuana stays in the bloodstream for a short time, blood tests are not usually used for this purpose, with the exception of automobile accidents and some roadside sobriety checkpoints. It can take an estimated 36 hours for marijuana to be undetectable in blood, though some reports suggest up to seven days with chronic use.
How Long Does Weed Stay in Your Hair?
Hair tests are not reliably able to detect marijuana use or to determine the amount consumed. Each centimeter of hair accounts for about a one-month period of time, so the detection period depends on hair length but is generally 90 days. First-time drug use in the last seven to 14 days cannot be detected due to the time that it takes for marijuana to reach the hair.
How Long Does Weed Stay in Your Saliva?
Like blood, marijuana is present in saliva for a short time. As a result, a saliva test could show current intoxication but would not indicate level of intoxication or impairment. Marijuana is detectable for an estimated 34 hours in saliva.
How Long Does Weed Stay in Breastmilk?
Breastmilk can contain THC for up to six days after use and can affect the newborn’s brain development, resulting in hyperactivity, poor cognitive function and other long-term consequences.
Will Weed Show Up on an Employment Drug Test?
Workplace testing often first entails an immunoassay test (EMRIT or RIA). If positive, it is then sent for gas chromatograph-mass spectrometer (GCMS), which is much more sensitive, so false positives are rare. At one time, ibuprofen (Advil, Motrin) would cause false positives for marijuana. However, today’s tests have eliminated that problem.
While marijuana is legal in some states, many employers have drug-free workplace policies. These workplaces often have random drug screening policies for current employees and routine testing for new employees to ensure their workplaces are drug-free. Your employment can be terminated for failing a drug test, even in states where marijuana has been legalized.
Detoxing From Weed
The only completely reliable way to pass a drug test is to stop using marijuana. While there are many tips and tricks for how to “beat” a drug test for marijuana, most have been shown to be urban legends.
Some of these questionable techniques include:
- Flushing your system: This method entails drinking fluids and urinating several times prior to a drug test, then taking vitamin b-12 to add color to urine. This serves to dilute THC metabolites but does not eliminate them.
- Exercise: Exercising or spending time in the sauna prior to a drug test can actually backfire by releasing THC metabolites from fatty tissue into the blood.
- Drug Screening Agents: Various companies sell substances or herbal teas claiming to “clean” the body’s traces of marijuana; however, there is little evidence to support this.
Marijuana Detox Facilities in Florida
Our treatment facilities offer medical and clinical treatments in a restorative setting where your successful recovery is our focus. In a medical detox program, your body slowly rids itself of the marijuana while under medical supervision. Doctors and nurses can quickly address any signs of withdrawal to make the process as safe and as comfortable as possible. Once patients have finished detox, they can transition directly into the full addiction treatment program.
Marijuana Addiction Treatment
The Recovery Village at Baptist Health offers a full continuum of care so that your recovery can be customized to your needs. After medical detox, marijuana addiction treatment might include either inpatient rehab where you live on-site, focused on recovery free of distractions, or outpatient rehab, where you live at home or in a sober living community and come to the facility regularly for appointments. Our partial hospitalization program (PHP) offers an intermediary step between inpatient treatment and outpatient rehab: more freedom during the day while keeping the benefit of medical supervision. Typically, outpatient rehab comes after successful inpatient rehab, where you have learned the skills necessary to live a marijuana-free life. We also provide mental health counseling for co-occurring disorders and aftercare for long-term recovery.
Depending on the level of care, we have a variety of indoor and outdoor amenities at our facility, including:
- Swimming pool
- Two fully equipped gyms
- Basketball courts
- Sand volleyball court
- Frisbee golf
- Horseshoe pits
- Multiple lounges with TVs
- Comfortable, hotel-style, semi-private rooms
Our licensed staff members are highly skilled in supporting our clients to find lasting recovery with compassionate care. As a member of the National Association of Addiction Treatment Providers and a Gold Seal Joint Commission facility, we are here to provide evidence-based, high-quality addiction treatment. Contact us today to start your journey toward a marijuana-free life.
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