Taking drug tests can be extremely stressful. Sometimes even innocent one-time marijuana users or second hand smokers can test positive and suffer from all the consequences. To feel confident and avoid big surprises, you may want to know how long marijuana (or other substances) stay in your body.

Quick Answer

If you are like most other people, substances can be detected in your systems from 5 to 90 days after a drug was taken. In every individual case, this figure may vary, depending upon drug strength, how often you used it and the type of test.

Top 4 Drug Tests

  • Urine drug test
  • If you are an occasional user, urine test can detect it within 7 days. If, however, you are a regular user, the detection time can extend for up to 100 days in some cases. Most often, it is 30 days though.

  • Hair drug test
  • This test is almost useless for one-time users (especially when it comes to cannabis). For regular users, however, it can detect substances for months or even years from the moment of the last intake for the heaviest cases.

  • Saliva drug test
  • Saliva drug test can detect substance within the first few hours after use and even measure its concentration. This test is used mainly for reasonable suspicion and post-accident cases.

  • Blood drug test
  • This test is the most precise one, but it typically works for up to 7 days. For one-time users, it is usually effective for only 24 hours.

Tests work differently, because they use different detection mechanisms. Some tests look for parent drug substances (saliva and blood tests), while others look for drug metabolites, which are the products released after a human body breaks drugs down (urine test), and some tests can detect both parent drugs and metabolites (hair drug test).

Factors Influencing Detection Time

The average detection times discussed above can vary individually, depending upon numerous factors, such as:

  • BMI (Body Mass Index)
  • The chemicals responsible for the drug effects on brain are often stored in fat cells. Therefore, the more body fat you have, the longer the drug substances stay in your systems.

  • Exercise
  • Exercising helps burning fat cells. Exercising weeks before a test helps washing substances out. However, if you exercise immediately before taking a test, it is more likely to detect drugs, which are first released into blood.

  • Metabolism
  • It influences the amount of body fat you have and the speed at which your body cleans itself out.

  • Hydration
  • If you do not drink enough water, there will be less liquid in your urine and blood. It means that the percentage of drug substances will be higher and they can be detected later.

  • Drug strength
  • The stronger the drug, the higher is percentage of substances and the longer it takes for your body to eliminate them.

  • Other factors
  • Age, gender, ethnicity, overall health condition and other factors all influence how long dugs can be detected in your systems.

The best solution is not to do drugs if you need to do a test. If you still worry, the facts discussed above may improve your chances for testing negative. For instance, lowering your body fat and staying hydrated can be a good idea, while attempts of quick fixes are usually ineffective.

Use the calculator below to find out average data on how long various drug substances stay in your body systems.

Choose drug below:

Mary Jane, Grass, Pot, Weed, Joint
2 days
2 days-11 wks
1-10 days
Up to 90 Days

Below is a list of pages containing detailed information on the most popular drugs, where you may learn how long they stay in your body systems.