How long can drug tests detect cannabis? Someday we may not need this information, but for now . . .
The most common drug tests used are urine, saliva and hair. Each test has a different detection time which is important to know. The urine drug test is the most commonly used because it is cheap and has a longer detection time than a saliva test. There are several very important factors that can influence how long THC will be present in your urine:
Frequency of Use
Since these factors will vary greatly for each individual, there are no definitive guidelines to tell you how long you can test positive for THC.
On a Urine Drug Test, THC will appear as a positive within 2-5 hours of use. How long it will still show on a urine drug test is estimated based on frequency of use, but does not take into account the weight and body fat of the marijuana user:
One Time User may show positive for 1-6 days
Moderate User may show positive for 7-13 days
Frequent User may show positive for 15 or more days
Heavy User may show positive for 30 or more days
Some Heavy Pot Smokers have reported being positive 45-90 days after quitting
On a Saliva Drug Test, THC will test positive within one hour of use, but may only show positive for about 12 hours after last use.
On a Hair Drug Test, THC will show up about 7 days after use and most hair drug tests will test for a 90 day period. However, THC does not always bind to the hair follicle which makes it not always considered an accurate testing method for marijuana use.
Learn more at the complete
Thanks to The Weed Blog for this infographic.