How Long Does Marijuana Stay in Your System? (Urine, Saliva, Hair)

The amount of time marijuana remains in your system depends on many factors, such as how much THC is in the marijuana, how often you use, how much you use, and your metabolism. If you’re a daily user, the drug can remain in your system for up to a month or longer.

Detox kits are not scientifically proven to speed up the detox process and may contain unknown chemicals that could be unsafe.

How Long Do the Effects of Weed Last?

The National Institute on Drug Abuse reports that the effects of marijuana include:1

  • Distorted senses.
  • Altered sense of time.
  • Mood changes.
  • Impaired coordination.
  • Trouble thinking and problem-solving.
  • Impaired memory.

Not all users of marijuana enjoy the experience. In fact, many people who use marijuana report unpleasant side effects, such as hallucinations, anxiety, and paranoia.1

The effects of marijuana can develop within minutes if the drug is smoked. If eaten, users may not feel any effects for a few hours. The effects normally last 3-4 hours but can last longer if the drug is eaten.4

Marijuana does not easily leave the body. Most cannabinoids, including THC, are stored in fat cells. This means that the effects of marijuana or hashish can reoccur for 12-24 hours after use because the chemicals are slowly released from fatty tissue.4

Detoxing From Cannabis (Weed)

There are several websites that claim to be able to help people eliminate marijuana from the body fast enough to pass a drug test. These allegedly rapid detox suggestions include drinking lots of water, green tea, cranberry juice, and even alcohol. Dietary supplements or over-the-counter medications, like vitamin B3, cayenne, milk thistle, or exclusive herbal remedies, are also marketed to help the body process marijuana faster.

However, none of these methods are scientifically proven to speed up the marijuana detox process, and some kits or drugs specifically marketed for this purpose may be dangerous and contain unknown ingredients. There is no proven method for accelerating this process.

The marijuana detox process can be tough for people who struggle with marijuana dependence, so contact a healthcare provider or enroll in medical detox at an inpatient or outpatient program for help safely withdrawing from this drug. People who struggle with an addiction should seek out a rehabilitation program or some form of therapy to help them recover.

How Long Does THC Stay in Your System?

The length of time that marijuana will show up on a drug test varies greatly from person to person.

Variables that can affect how long marijuana will show up on a drug test include:5

  • Dose of THC ingested.
  • How often the person used.
  • Timing of drug test relative to last use.
  • Rate of release of THC or other cannabinoids from tissue.
  • Level of hydration.

The amount of THC in marijuana will affect how long it takes for the body to metabolize the drug. However, keep in mind that other factors can affect how long marijuana stays in your system. These include the amount of marijuana you used, how you used it, how often you used, and your metabolism. The amount of THC in the plant is just one variable that will determine how long the drug remains in your system.9

How Long Does Marijuana Stay In Urine?

The amount of time that marijuana will show up on urine screenings depends largely on how often the individual uses. The following are some basic guidelines on how long marijuana will show up on a urine test based on how often you use:5

  • Less than twice per week smoker: 1-3 days.
  • Several times per week smoker: 7-21 days.
  • Daily smoker: 30 days or longer.
  • Oral ingestion (edibles): 1-5 days.

How Long Does Synthetic Marijuana Stay in Your System?

Synthetic cannabinoids can be detected in drug tests. They can be detected up to 72 hours in urine and up to 24-48 hours in saliva.6

That said, some synthetic cannabinoids could have longer long half-lives. That means they could have longer effects and show up in a urine test beyond the timeframe listed above. In addition, the batches of synthetic cannabinoids can vary both in terms of the substances present and their quantity. This increases the risk of overdose.6

How Long Does Marijuana Stay in Blood?

Depending on factors such as how frequently a person uses marijuana and how they metabolize it, this specific substance can be detected in blood anywhere from a few hours to a few weeks after use.Consider the following:9

  • Infrequent marijuana use – Someone who uses marijuana infrequently can have it detected in their blood for 3 to 4 hours after use. The metabolized result of THC, known as 9-carboxy-THC, can be detected in the blood of those who use marijuana infrequently for 2 to 3 days after use.
  • Frequent marijuana use – Those who participate in frequent marijuana use can have it detected in their blood for 4 to 8 hours after use. The 9-carboxy-THC can, however, be detected for up to two weeks in those who frequently use marijuana.

Other Types of Drug Screens

THC can be detected in saliva within minutes and up to 2 days.7 Hair testing can typically detect drugs such as marijuana for months after use (up to 90 days).8

Can You Fail a Drug Test From Secondhand Smoke?

You are at risk of failing a drug test if you inhale secondhand marijuana smoke. But the odds are small.

Studies show that very little THC goes into the air when a person exhales marijuana smoke. Research suggests that unless you are in an enclosed space and you inhale lots of smoke for hours at close range, you probably won’t fail a drug test.1

How is Marijuana Used?

Marijuana refers to the dried leaves, flowers, stems, and seeds of the cannabis sativa or cannabis indica plant. These plants contain THC and other similar compounds, which are responsible for the mind-altering effects of the drug.1

marijuana use and sales have increased throughout the yearsThe most common way to use marijuana is to smoke it through a joint, blunt, bowl, or bong. Some people also use vaporizers to avoid inhaling the smoke.1

People also mix marijuana in food (edibles), such as brownies, cookies, or candy, or brew it as a tea. Edible forms of marijuana are growing in popularity. In California alone, edible sales reached $180 million in 2016, and sales in the U.S. and Canada could top $4.1 billion by 2022.1,2,3

A newer method is to smoke or eat different forms of THC-rich resins.1

Get Help for Marijuana Addiction

If you or someone you love is struggling with addiction and are ready to take the first steps towards recovery, call us today at . Desert Hope, American Addiction Centers’ Las Vegas drug rehab facility, is ready to help you get the treatment you need today.

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