How long does cocaine stay in urine drug screens (UDS)?

From the Guidelines

Cocaine typically stays in a urine drug screen (UDS) for 2-4 days after last use in occasional users, though it can be detected for up to 7-14 days in heavy or chronic users. The primary metabolite tested for in urine is benzoylecgonine, which has a longer half-life than cocaine itself, with a urinary half-life of 6 to 8 hours 1. Detection time varies based on several factors including dosage, frequency of use, metabolism rate, body mass, hydration level, and kidney function.

Key Factors Influencing Detection Time

• Dosage: Higher doses result in longer detection times
• Frequency of use: Chronic users may have longer detection times due to accumulation of metabolites
• Metabolism rate: Individual variability in metabolism can affect detection time
• Body mass: Detection time may be longer in individuals with higher body mass
• Hydration level: Drinking water may slightly speed up clearance, though this won't significantly reduce detection time
• Kidney function: Impaired kidney function may result in longer detection times The standard cutoff concentration for most urine tests is 300 ng/mL 1. More sensitive laboratory tests may detect cocaine metabolites for longer periods than rapid screening tests. According to a recent guideline, a person’s urine typically tests positive for cocaine within 1 to 4 hours of consuming the drug and will continue to test positive for 2 to 4 days 1. It's also important to note that hair tests can detect cocaine use for up to 90 days, blood tests for 1-2 days, and saliva tests for 1-2 days after use.

From the Research

Detection Time of Cocaine in Urine

• The detection time of cocaine in urine can vary depending on several factors, including the dose and route of administration, metabolism, and the sensitivity of the method used 2, 3.
• In general, the detection time of a single dose of cocaine in urine is approximately 1.5 to 4 days 2.
• In chronic users, cocaine can be detected in urine for approximately 1 week after last use, and in extreme cases, even longer 2, 4.
• The detection time of cocaine in urine can be influenced by the cut-off value used, with higher cut-off values resulting in shorter detection times 3, 5.
• Creatinine normalization of benzoylecgonine equivalents can increase the detection time of cocaine in urine, but may not reduce the fluctuation of benzoylecgonine equivalents across successive specimens 5.

Factors Affecting Detection Time

• The dose and route of administration can affect the detection time of cocaine in urine, with higher doses and certain routes of administration resulting in longer detection times 3, 4.
• Metabolism and renal clearance can also influence the detection time of cocaine in urine, with individual variations in these factors resulting in different detection times 2, 5.
• The sensitivity of the method used can also affect the detection time of cocaine in urine, with more sensitive methods resulting in longer detection times 2, 3.

Quantitative Urinalysis Testing

• Quantitative urinalysis testing can be more sensitive to short-term cocaine abstinence than qualitative testing, but requires careful selection of a criterion for distinguishing new use versus carryover from previous use 6.
• The decrease in benzoylecgonine concentration over time can be used to estimate the likelihood of a sample occurring during a period leading to a cocaine-negative urine sample 6.
• The number of days required to produce a cocaine-negative sample following a positive sample can range from 1 to 10 days and is significantly correlated with the starting benzoylecgonine level 6.