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How long do drug tests work? 

On Behalf of | Aug 14, 2024 | Drug Charges

With some types of drug and alcohol testing, the results are immediate. A breath test can detect the presence of alcohol as long as it’s still in a person’s system.

But these types of tests usually only work for alcohol impairment. For other types of drug use, urine testing may be used. How long this will demonstrate evidence of past drug use depends on a variety of factors, such as the type of drug that was used and how often the person uses it.

Marijuana testing

For example, urine testing can demonstrate the use of marijuana for three days, even if the person only used it once. But if they are a heavy marijuana user, there may be evidence for up to 30 days.

To help show how it varies from one drug to the next, here are some of the common drugs that may be detected and the window for finding them in urine tests:

  • Amphetamines: 48 hours 
  • Cocaine: Up to four days 
  • Heroin or codeine: 48 hours 
  • Oxycodone: Up to four days 
  • Morphine: From 48 to 72 hours 
  • PCP: Eight days 
  • Synthetic marijuana: 72 hours 
  • Barbiturates: Between one day and three weeks

Additionally, it’s important to remember that urine testing is not the only type that the authorities use, and it often has the smallest window for drug detection. For example, many drugs will show up in hair follicle tests for up to 90 days.

Your defense options

You can see how this type of drug testing is much different than breath tests for alcohol. If you find yourself facing charges for drug possession or related activities, be sure you understand your legal defense options.