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Cannabis 101: How Long Does Cannabis Stay in Your System?

One of the most common questions we get asked as cannabis care providers is: How long does cannabis stay in your system? It’s an important question, for a number of reasons: It helps us calculate our proper dosage, gauge its effects, and—in the event our employer institutes mandatory drug testing—to be aware of the threshold of detectability.

Keeping in mind that there are several kinds of tests for cannabis and that the results can vary from person to person, here’s what we know about this all-important question. 

How Long Does Cannabis Stay in Your System? The Variables

When you consume cannabis, THC—the most prevalent cannabinoid, and the one most tests are designed to detect—enters your bloodstream and is broken down into molecules called metabolites. Like its psychoactive “high,” the THC itself dissipates fairly quickly, usually within a few hours. But those metabolites stay in the body for some time, and at least one of them, called THC-COOH, is detectable days or even weeks after the cannabis was consumed. 

How Long Does Cannabis Stay in Your System

Unfortunately, the question of exactly how long THC-COOH is detectable depends on several factors:

How often you ingest cannabis: As you might expect, those who regularly consume cannabis are more at risk of being detected, because metabolites like THC-COOH tend to accumulate over time. Those who use infrequently—like once a week or less—should be at reduced risk of detection.

Metabolism and body fat: Just as we all react to cannabis differently, our metabolism helps determine how quickly those cannabis artifacts are eliminated. Because THC is fat-soluble, in general those people with a higher proportion of body fat will retain those THC metabolites for longer.

How Long Does Cannabis Stay in Your System? Methods of Testing

This is an important question. Each method of testing—by saliva, urine, or hair—has a specific window of greatest accuracy. Given that the window is affected by the variables we named above, here are our estimates of accuracy.

Methods of Cannabis Testing

Saliva Test

This type of test—usually performed using an oral swab—yields the shortest-lived results. If you’re tested with this method, you can expect THC to be detectable in your system for 24 hours if you’re an infrequent user, or up to 72 hours if you’re a more regular one.

Urine Test 

This is generally the most-used test method when it comes to workplace compliance. Within reason, you can expect THC to be detectable in your system:

  • For a single use (as in, once in a month): Up to 8 days
  • For regular use (4-6 times in a month): Up to 15 days
  • For frequent use (10 – 15 times  in a month): Up to 30 days
  • For heavy use (20+ times in a month): Up to 45 – 77 days 

Hair Test

Type of Cannabis Test

This type of cannabis test is designed to identify chronic users. That’s good news for light or infrequent users, because there’s a reasonable chance they won’t be detected at all. But for regular or heavy users, the outlook isn’t very good, as the standard window of accuracy is roughly 90 days. 

If you have any questions about how long cannabis stays in your system or any other cannabis-related topics, drop us a line. We’re here to help!