How Long Does Hash Stay in Your System?

Hash in Your Blood, Urine, Hair, & Saliva

dropper of hemp oil on a countertop next to lemon

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Hash, which is short for hashish, is a preparation of marijuana made from the resin of the buds of the cannabis plant. Hashish oil, or hash oil, is the strongest form of marijuana since it's so concentrated, with a pound of marijuana yielding just an ounce or two of hash or hash oil.

It can be used in preparing edibles, smoked, or ingested in other ways. The psychoactive ingredient in hash and marijuana is tetrahydrocannabinol (THC).

Since the processing of marijuana into hash oil isn't standardized, even in legalized production, it's difficult to know just how much of the active ingredients are present in the hash oil. It can contain anywhere from 15 percent to 60 percent THC.

Hash or hash oil may be used as a form of medical marijuana and may be allowed in states where marijuana has been legalized.

How Long Does Hash Stay in Your System?

Blood: Up to 4 hours

Urine: Up to 30 days

Saliva: Up to 72 hours

Hair: Up to 90 days

How Long Does It Take to Feel Effects?

THC enters your body's bloodstream rapidly after smoking hash oil. You feel the effects within minutes and they peak in about 30 minutes. If hashish is ingested, such as in baked goods or edibles, it takes longer to be absorbed into the blood, usually from 20 minutes to an hour and a half.

Once in your system, you may feel like the effects have passed after two to three hours, although there can be some impairment for as long as 24 hours. The timeframe is extremely variable. It depends on the concentration of THC, which, as noted before, is not standardized with hash oil, even where it can be produced and purchased legally.

If you're a light user, the effects of THC on attention, concentration, and working memory generally pass six hours after ingesting or smoking THC-containing products. During this period, your psychomotor skills are affected, so you shouldn't drive or operate machinery. In a traffic stop, you could be charged with DUI, even if you have a prescription for medical marijuana.

If you're a heavy user, there can be residual effects for as long as 28 days after you stop using THC-containing products. The physical side effects of hash oil include increased heart rate, red eyes, dry mouth, increased appetite, and vasodilatation (widening of blood vessels, which decreases blood pressure).

Due to the uncertain concentration of THC in hash oil, you should be cautious about the amount you take for medical purposes. Taking a large dose may result in hallucinations, paranoia, altered mood, memory problems, anxiety, and altered sensation: Fortunately, these effects will wear off over the course of a few hours.

THC can interact with other drugs, including alcohol, as well as a number of medications like blood thinners and anti-anxiety medications. If you're on any medications, discuss your use of hash oil and other THC-containing products with your doctor as it may influence your dosages.

How Long Does Hash Last?

The half-life of hash is how long it takes for half of the drug to be metabolized and eliminated from the bloodstream. Some THC metabolites have an elimination half-life of 20 hours. The half-life of fat-stored THC is about 10 to 13 days, meaning there is half of the original amount left at this time.

Some of the THC in your bloodstream is rapidly metabolized into more than 80 different chemicals, known as metabolites. A portion of these is then excreted in your urine. But THC and its various metabolites are also stored in body fat and these remain in your system for much longer. These metabolites accumulate, so if you use hash or hash oil every day, you will have more stores of THC in your body and it may take much longer to eliminate them from your system. Some of the THC is stored unchanged, so when it's released from fat into your body, it can again exert its psychoactive properties as well as be metabolized and excreted in your urine.


Blood tests are rarely used to detect THC, since it can only be detected in the bloodstream for about three to four hours.


In general, the detection windows for THC in a urine test can range from three to 30 days, depending on how often you use the drug.

  • One use: 3 days
  • Moderate use (4 times a week): 5 days
  • Daily use: 10 days
  • Daily use over an extended period of time: 30 days


THC typically remains in saliva for one to three days, or until it's fully swallowed. Drinking water, brushing your teeth, and using mouthwash may speed up this process.


THC can also be stored in your hair follicles, where it may be detected for up to 90 days. This long elimination period is of concern for a medical marijuana user who may need to take a urine drug screen.

False Positives

Previously, over-the-counter non-steroidal anti-inflammatory (NSAID) medications like Advil, Motrin, and Nuprin caused false positives on tests used to detect THC. The tests have been adjusted, however, and this is no longer a problem.

Factors That Affect Detection Time

How long THC stays in your system depends on a variety of factors, including age, amount of body fat, hydration, physical activity, and how frequently and how much hash you use.

Body Mass Index

Although not perfect, BMI or Body Mass Index is a method of estimating body fat levels based on a person's weight and height measurement. Since THC tends to accumulate in fatty tissues, people with a higher BMI may metabolize THC more slowly, causing longer detection times than a person with a lower index.


Since women tend to have higher levels of body fat than men, they may metabolize THC at a slightly slower rate.

Frequency of Use

If you use hash one time, it might be detectable for only a short period of time, whereas heavy or very frequent drug use can cause concentrations in the system that can be detected for lengthy periods of time.

Metabolic Rate

If you have a higher metabolic rate, the shorter the time a drug can be detected in the body. Metabolic rates can be affected by your age, physical activity level, and certain health conditions.


If you’re dehydrated, you’re likely to have higher concentrations of THC in the body. That said, drinking lots of water will only dilute a drug test, which in most cases, will mean you’ll need to retake it. 

How to Get Hash Out of Your System?

There is no reliable, quick way to remove THC from your body, despite what people and products claim. Certainly, drinking a lot of water and liquids or exercising vigorously may help, but you’ll still need time for your body to break down and eliminate THC metabolites from your body. 

Various companies sell drinks and herbal supplements like creatinine or vitamin B-12 that claim to dilute your urine or “clean” the body’s system, but these drug screening agents may take time and are not always reliable. 

Symptoms of Overdose

Medical professionals don't yet know how much THC it takes to overdose. That said, THC toxicity has been found to result in psychotic episodes, uncontrollable vomiting, and heart arrhythmias. THC overdose can happen easier with edibles, as it takes longer for your body to absorb the THC and feel the effects. This can prompt users to take more, thinking they didn't get enough.

Getting Help

You can become psychologically addicted to THC and experience signs of withdrawal if you stop suddenly. While these symptoms are milder than many other drugs, they still exist and may include cravings, mood swings, sleep disruptions, headaches, and digestive troubles. The frequency and amount of hash used prior to stopping will affect the severity and length of the withdrawals.

If these symptoms become intense enough to drive you to relapse to find relief, you'll want to seek guidance from a healthcare professional who can offer coping strategies for the physical side effects. It's also smart to get help if you find you can't get through your day without hash; this may be a sign of a substance use disorder.

Setting up an appointment with a mental health professional or visiting an online or in-person support group can help you deal with the psychological symptoms of hash withdrawal.

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Article Sources

  1. Sharma P, Murthy P, Bharath MM. Chemistry, metabolism, and toxicology of cannabis: clinical implications. Iran J Psychiatry. 2012;7(4):149–156.

  2. National Institute on Drug Abuse. Effects of Marijuana on Brains and Bodies

  3. Oberbarnscheidt T, Miller NS. Pharmacology of Marijuana. J Addict Res Ther S11:012. doi:10.4172/2155-6105.1000S11-012

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