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How Long Do Drugs Stay in Your System?

Table of contents

1. Variables to take into account
2. How long does marijuana stay in your system?
3. How long does alcohol stay in your system?
4. How long does heroin stay in your system?
5. How long does crack stay in your system?
6. How long does cocaine stay in your system?

This article covers different drug variants, from marijuana to alcohol to heroin, and how long they stay in your system. You may need this information if you’re expected to do a drug test for any reason and you want to ensure the results are clean.

Variables to take into account

how-long-do-drugs-stay-in-your-system
Image via Flickr by Magnum, PPI

Drug test results are determined by analyzing a person’s urine, saliva, hair, or blood, but several factors can affect how long drugs stay in your body and if the results are interpreted correctly. Perhaps one of the most famous examples is an instance of diet affecting your urine; if you eat a poppy seed bagel before a urine test, you will have opium in your urine, as poppy seeds naturally contain trace amounts of the drug. Avoiding food or drinks that could taint the results of your sample is an important consideration to make when you are undertaking a drug test.

You should also be wary of taking painkillers because these can show up in drug tests. If there’s any medication you have to take, inform the person conducting or analyzing your test so they can also take that into account.

You need to consider certain variables when judging how long drugs might stay in your system. Your weight, hydration, drug tolerance, and urine acidity can all play a part in the longevity of drugs in your body. If you’re concerned and would like a definitive answer, you can order drug tests to do at home or consult your general practitioner. If your job requires you to be drug tested, such as working as a train driver, then it is important to pay attention to what you are eating or drinking.

How long does marijuana stay in your system?

Urine drug tests are the most common form of analysis for marijuana in a person’s system. Depending on how regularly you use marijuana, it can stay in your body anywhere from three to 30 days. Cannabis is fat soluble, so your weight will affect this number. Here’s a general guideline for how long marijuana remains in your system, based on how often you partake:

  • Up to three times a week: Three days.
  • Four times a week: Five to seven days.
  • Daily: 10 to 15 days.
  • Multiple times daily: Up to 30 days.

Marijuana usage can also be detected through a blood test. In most cases, traces of the drug are apparent only in the first couple of days, although there have been cases of cannabis being found in the bloodstream as long as 25 days after consumption. Similarly to urine tests, how often you smoke and your body weight can affect this time frame.

Saliva tests can also detect traces of marijuana in a person’s body. Cannabis can enter a person’s mouth through second-hand smoke, but metabolites will be present only if the person has smoked. Here’s a guide to help you figure out how long cannabis can be present in your saliva:

  • Occasional user (up to three times a week): one to three days.
  • Frequent user (daily): one to 29 days.

This test is most likely to be used in roadside checks. Hair tests can detect drug usage three months after the initial consumption. Honesty and foresight are important with these tests.

How long does alcohol stay in your system?

Depending on your body and the test used, the time alcohol remains in your system varies from one person to the next. Breathalyzers are also used to detect alcohol in the body. Here’s a general guide for the different tests and how long after consumption alcohol is detectable:

  • Blood: Up to six hours.
  • Breath: 12-24 hours.
  • Urine: 12-72 hours (depending on how new the testing method is).
  • Saliva: 12-24 hours.
  • Hair: Up to 90 days.

Age, weight, sex, and diet can all affect how long alcohol remains in your system.

How long does heroin stay in your system?

Heroin is fast-acting with a short half-life, so it can often be difficult to detect in your average drug test. The metabolites produced when the body breaks it down can usually show up in standard screening tests one to four days after consumption. Here’s a general guide for the different tests and how long heroin remains in your system:

  • Blood: Up to six hours.
  • Urine: Up to three days.
  • Saliva: Up to 24 hours.
  • Hair: Up to 90 days.

Because heroin is illegal, it is often mixed with other substances, which can affect its purity and therefore affect how long it stays in the blood. As with other drugs, the user’s personal physiology can also affect the longevity of heroin in the body.

How long does crack stay in your system?

Urine tests are most commonly used to detect crack cocaine in the body, though it can be detectable with other tests. Here’s a general guide for the different tests and how long after consumption crack remains in your system:

  • Saliva: 24-48 hours.
  • Blood: Up to one day.
  • Urine: One to four days.
  • Hair: Up to 90 days.

As with the other drugs mentioned, your weight, age, sex, and personal drug tolerance can affect how long crack stays in your system.

How long does cocaine stay in your system?

Detecting cocaine in the body varies based on several factors, such as length and frequency of usage, the type of test used, and personal physiology. Here’s a general guide for how long after taking cocaine certain tests can detect it in your system:

  • Blood: 12 hours for cocaine, 48 hours for metabolites.
  • Hair: Months.
  • Saliva: One to two days.
  • Sweat: A few weeks.
  • Urine: Two to three days or up to two weeks for heavy users.

To get more specific answers based on your body, we recommend visiting your GP.

The Canadian Centre for Addictions (CCFA) is here to help

The Canadian Centre for Addictions (CCFA) offers a full range of quality services that give our visitors flexible therapy and counselling for drug and alcohol addiction. Contact us now and ask about our addiction program.