Avoiding Negative Dilute Drug Test Results

If you go for a drug test and your result comes back as negative dilute, your employer may ask you to for another drug test.  This will certainly be inconvenient for you.

You can learn here how to avoid a negative dilute drug test.

Basically, when your urine specimen for a drug test comes up dilute, you have drank too much water in advance of the test.  You should be careful not to overconsume fluids prior to a drug test.  An extra glass of water is about all you need. If you drink too much fluids, then you will more than likely end up with a dilute specimen.

A positive dilute drug test result is always positive.   When you have a negative dilute drug test results, many employers will require you to go back for another drug test.

Dilution is caused by adding fluid to the sample or by drinking large amounts of fluid which may dilute the specimen.  If you are adding fluid to your sample, it is likely you are trying to cheat on the drug test.

A dilute specimen, by definition, is a urine specimen that has a creatinine of greater than 5 mg/dl or less than 20 g/dl and specific gravity is less than 1.0010 (or greater than 1.0200). These 2 tests are routinely performed on every urine sample that is tested at the Lab. If the specimen meets the above 2 criteria, it is reported as a “Dilute specimen”. When a urine specimen is “dilute”, it is possible that drugs in their system may not be detected.

Don’t be alarmed if your employer tells you the drug test result is a negative dilute result.  This should never be a reason for you to be terminated or not get the job.  If this does happen, call an attorney.  You should never be fired because you drink a lot of water but you do need to be able to produce normal human urine with the appropriate creatinine and specific gravity levels.  Failure to do this many be suspicious.

If you add fluids to your urine specimen, this could be grounds for termination of employment or perhaps not getting the job.

It is best if you go for the drug test first thing in the morning.  Have some coffee and a glass of water and you will be fine.  Don’t overconsume water or other fluids.

One can never assume that a dilute specimen indicates cheating on the drug test.  The problem with assuming that dilute urine is always due to attempted cheating is that many individuals drink large amounts of water for health reasons or simply to “be prepared” to provide a urine sample.

As a participant providing a urine sample, you can follow some simple guidelines to avoid providing dilute urine.  These are:

  • Avoid all diuretics—including caffeine—the day of the drug test until AFTER the collection is done.
  • Go to the collection site while the first morning urine is still in your bladder to use this as the specimen.
  • If this is NOT possible than you should empty your bladder approximately 2 hours prior to your planned arrival at the collection site.
  • During that time, you should NOT consume more than 24 oz. of fluid and the fluid you do consume should be a substantial fluid—milk, smoothie, tomato juice—and/or you eat a protein high meal or snack—egg, cheese, meat.


By following these guidelines, you will help to avoid dilute and abnormal urines and ensure that the result of your test provides a valid indicator that you are drug free.

More on dilute drug test urine specimens:

What Is A Negative Dilute Drug Test Result?


Dilute Specimens In Employer Drug Testing


Video Blog: Confused About “Negative Dilute”?

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Meet The Author: Joe Reilly

Joe Reilly has spent many years in the workplace drug testing field, currently serving as president of National Drug Screening. He brings his knowledge to offer consulting, training, and expert witness services to employers, labs, specimen collectors, TPAs, and others involved in workplace drug testing

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