Last updated : July 7, 2025
If you’re scheduled to report for a company drug test, you probably received some information about what to do or not do before the test. Still, questions arise which may be the reason you clicked into this article. So we won’t beat around the bush! Yes. Coffee can dilute your urine specimen.
Actually, consuming a mass quantity of any liquid before a drug test dilutes the urine. In fact, in the early days of drug testing, it often resulted in a false negative test result. Drug users would intentionally drink lots of water or some other non-alcoholic beverage to dilute their specimens. It didn’t take long for the industry—not to mention, employers—to catch on to the ruse.
How that boiled down
As laboratory equipment became more sophisticated, scientists were able to discern a way to determine if a urine specimen was diluted.
When excessive amounts of liquid pass through the body, it throws off the urine’s pH levels. Drug tests now measure the creatinine level in the specimen which shows the pH level. If it falls below normal, the sample is diluted. Technicians mark the test as “inconclusive.”
Whether or not there are drugs found in the specimen, employers often treat an inconclusive drug test the same as they treat a positive result. The employee is immediately terminated. However, employers may make exceptions when this result is due to a diluted specimen and allow the employee or job applicant to retest.
Positive and negative dilute
When an employee’s test sample shows that it’s diluted, it’s either a positive dilute or a negative dilute.
Negative dilute
A negative dilute means that no drugs were detected in the employee’s system. Even so, the sample indicated the creatinine level was too low. That makes it impossible to establish a negative drug test result with certainty.
Of course, a diluted sample doesn’t immediately indicate the employee was masking drug use. It may just have been a “need a big cup of caffeine” kind of morning. Or, they may suffer from shy bladder syndrome. If that’s the case, the only intent may have been to increase the odds that they could provide a specimen at all! Lastly, it could have happened because someone wasn’t aware it was possible to affect the drug test by drinking “too much.”
Many employers drug policies state that a negative dilute requires a second test. Employers of the safety-sensitive workforce are mandated to allow a second test too—and it’s directly observed. On the flip side, the employee could also be terminated immediately.
Positive dilute
When an employer sees a positive dilute result, it indicates two things:
- The employee had drugs in their system.
- They more than likely tried to hide it.
Some employers of the general workforce allow a second chance if the employee completes a rehabilitation program. Other companies terminate the employee immediately.
Can coffee help a cheater pass?
Drug users looking for a way to cheat the results can find a couple of specific coffee-related myths floating around the internet.
The first one we found says to mix Folgers—no other brand will work—coffee with water. The instructions say to pour the mixture into a vial and hide it on your person. Then, they simply pour the mixture into the specimen cup and turn it in. *insert lmao emoji here* Good luck with that one.
So, they’re actually claiming that lab techs can’t discern the difference between Folger’s coffee and urine. Wow. Drug users must be high and desperate to think this technique could even be feasible.
Another says that if you lay off all caffeinated beverages for a week and then drink specific amounts of coffee for a specific number of days before the test, you’re guaranteed to pass.
Oh, brother. Will they never learn?
Someone should tell these people that in reality, either method offers about as much help in passing a urine drug test as any other drug testing myth. The best way to “beat” the test is to not have drugs in your system.
What if you get the jitters?
Downing super-sized lattes can certainly affect behavior. Talking a mile a minute or getting a case of “the jitters” is a known side-effect. Still, being jittery isn’t automatically considered a direct result of someone who consumed too much caffeine. It is a telltale sign, however, that something is amiss. Testing technicians are trained to pick up on signs that point to someone trying to fake a drug test result.
A red flag raised by nervous behavior leads to a heightened sense of awareness regarding the employee being tested and the specimen they present for submission. But, no worries if you’re drug free, you’re good to go.