Tick-Tock: How Long Do Drugs Stay in Your System?

Tick-Tock: How Long Do Drugs Stay in Your System?

If your employer surprises you with a drug test Monday morning, will your activities from Friday night show up? The answer depends on many factors. What substance did you use? How much did you take? How fast is your metabolism? The timeline will vary quite a bit for each person and situation. But based on typical body processes, we know the following:


  • Blood: 336 hours (2 weeks)
  • Urine: 27 days (on average)
Why is there an ‘average’ number for urine tests? Because these results can vary from as little as five days to as long as 63 days after use. Let’s take a look at why. Urine tests used for detecting marijuana are actually in search of THC-COOH. This is the chemical left over after your body processes THC (the chemical in pot that causes users to feel high). Urine tests are designed to detect THC-COOH, since it would only be present if you’ve used cannabis. How long this chemical is detectable is largely dependent on how often you use marijuana. Let’s say you are a one-time user. This is usually only detectable for 5-8 days. But, if you are a long-time user who smokes marijuana daily, it will stay in your urine for 49-63 days. Using cannabis 2-4 times per week and then stopping makes your urine positive for marijuana for 11-18 days. Smoking it 5-6 times a week causes it to stay in your urine for 33-48 days. The large range in each of these scenarios is due to differences in each person’s metabolism and how much was smoked each time.


  • Blood: 48 hours
  • Urine: 3-4 days (longer for chronic users)
Just like marijuana, cocaine is detectable for longer periods of time in heavy users. This is because long-term users’ bodies actually store the drug. Cocaine is toxic to the body and therefore difficult to process. With continued use, it becomes stored within fatty tissues like the liver and continues to build up there. As a result, it takes much longer for the body to detoxify from cocaine. Chronic users can expect a positive urine result up to two weeks after use. Other factors that can affect this timeline include size of dosage and the mode of administration. Of course, the bigger the dose, the longer it stays in your system.


  • Blood: 12 hours
  • Urine: 3 days
Heroin is fairly short-lived in your body (but has very long-lived dangerous effects). It is only detectable in blood for a few hours; in urine, it’s present for up to three days. However, as with other drugs, this timeline can vary due to many factors. Height, weight, age, body fat, dosage, metabolism and the health of your liver and kidneys all affect how long heroin remains detectable in your system. The more you take, the longer it’s in your body. Healthier organs can process it faster - so can a faster metabolism. Of course, with continued heroin use, the body suffers damage and these body processes drastically slow as a result of inefficiency.