Urine tests are commonly used to screen for drug use, to monitor health conditions, and to diagnose medical issues. Diluting urine by drinking extra fluids is sometimes attempted by people who want to produce a clean urine sample. However, laboratories test for diluted specimens, so drinking a lot of water is often ineffective for masking drug use or medical conditions.
What is urine dilution?
Urine dilution refers to making urine less concentrated by consuming extra fluids, usually water. This decreases the levels of detectable substances in the urine like drugs or their metabolic byproducts. The goal is to get the concentrations below the cut-off levels used in testing so a sample screens as negative.
Diluted urine has higher than normal water content, resulting in a light color and low specific gravity. Specific gravity compares the density of urine to the density of water. Normal values range from 1.005 to 1.030. Diluted urine may dip as low as 1.000 or 1.001.
Why do people try to dilute urine?
The main reasons people try to dilute urine samples are:
- To pass workplace drug tests after using illegal drugs like marijuana or cocaine
- To hide medical conditions like diabetes or kidney disease
- To pass athletic doping tests after taking banned performance enhancing drugs
By drinking excessive amounts of fluid before providing a urine sample, people hope to drop drug or metabolite concentrations below the threshold needed for a positive test result. This allows them to pass drug tests and avoid consequences.
Some people also dilute urine in a misguided attempt to speed up excretion and detoxification. However, this is an ineffective strategy. The kidneys constantly filter toxins out of blood, so urine dilution does not enhance clearance.
Does diluting urine work to pass a drug test?
Diluting urine is often ineffective for beating drug tests. Laboratories screen specimens for dilution and sometimes reject diluted samples. Telltale signs include:
- Pale, watery urine
- Low specific gravity, typically less than 1.003
- Low creatinine concentration, normally greater than 20 mg/dL
Creatinine is a waste product of muscle metabolism that is excreted in urine at relatively constant rates. Low creatinine along with low specific gravity indicates excess fluid intake.
When dilution is detected, the sample may be rejected and a retest requested. Repeatedly providing diluted specimens can be viewed as tampering with a drug test. This may be treated the same as a positive test by employers.
While some hydrating can lower drug metabolite levels, it takes aggressive over-hydration to dilute urine enough to beat a drug test. This puts a person at risk of dangerously low sodium levels (hyponatremia) and requires cessation of exercise to avoid symptoms like disorientation, nausea, and fatigue.
Are there ways to successfully dilute a urine sample?
There are a few methods people attempt to dilute urine for a drug test while avoiding detection:
- Taking creatine supplements – Since low creatinine levels can reveal dilution, taking creatine before a test may maintain normal creatinine readings even when urine is diluted. However, high creatine with low specific gravity still suggests dilution.
- Adding adulterants – Chemicals like bleach, vinegar, nitrites, or glutaraldehyde may interfere with drug tests. However, most labs check urine for adulterants.
- Substituting urine – Bringing in urine from someone else or synthetic urine can produce negative test results. But labs check temperature and now also DNA to detect substitutions.
While these methods may work occasionally, they carry risks. Tampering with a drug test is often equivalent to failing it. It’s safer to avoid drug use or find employment that doesn’t drug test.
Can you dilute urine for a medical test?
Diluting urine prior to a medical test falsifies results and makes it difficult to diagnose conditions. Doctors can only make accurate assessments when they have unadulterated lab results to interpret.
If urine is excessively diluted, medically important information is washed out. A urinalysis helps identify issues like:
- Dehydration or kidney dysfunction – from specific gravity, creatinine, proteins
- Bladder infections – from leukocyte esterase, nitrites, white blood cells
- Diabetes – from glucose in the urine
- Liver disease – from bilirubin levels
Low levels due to dilution may mask underlying medical problems. Diluted urine should always be rejected by laboratories when ordered for medical testing.
Some people try to dilute urine to hide medical conditions like diabetes or kidney disease. However, treatment depends on getting an accurate diagnosis, so it is important to provide normal undiluted samples.
Conclusion
While diluting urine may seem like an easy way to beat a drug test, laboratories can usually detect diluted samples. Providing diluted urine for medical tests also invalidates results. An undiluted sample should always be given unless over-hydration is medically advised by a doctor. Being well hydrated is healthy, but intentionally diluting urine carries consequences and potentially hazardous side effects.