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How long do drugs stay in your system? With random testing, it doesn’t matter.

How long do drugs stay in your system?

Tristan HoagVerified


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Types of drug tests

The type of drug test being taken will have a big impact on how long different drugs can be detected in your body.

Anything that you take into your body will leave traces that can be detected, and this includes alcohol and drugs. Depending on the screening method being used, these traces can be identified for days, weeks or even months after you used the substances. An increasing number of employers are requiring drug tests of their employees, causing many people to wonder, "How long do drugs stay in your system?"

The Experts on JustAnswer are frequently asked questions regarding the length of time different drugs can be detected, and by analyzing that data, some interesting patterns can be detected.

Why drug testing?

As the number of workplaces that require drug testing increases, odds are you'll find yourself being tested at some point. Any job that involves operating heavy machinery is likely to require drug testing, as will jobs in security. Even if your employer doesn’t require testing, and you never have trouble with law enforcement, you can still be tested in a hospital after an accident, or by a school in order to participate in sports or other activities. The military regularly drug tests active duty service members.

Drug tests are intended to discourage the use of drugs and alcohol, but they are also meant to protect the issuing organization from the legal and financial collateral damage caused by substance abuse. It can also function as a method of identifying people in need of early intervention.

Most organizations adhere to the Substance Abuse and Mental Health Services Administration's (SAMHSA) guidelines for drug testing, although they aren’t required to do so. While some companies will perform drug tests at regular intervals, others prefer random drug testing to try and catch employees off guard.

Types of drug tests

Drugs can be detected in your body in a number of ways, and there are different types of drug tests that can be used to screen for them. The type of test used will have an impact on the amount of time that different drugs can be detected in your system. Some of these testing methods include:

Blood tests: Taking a blood sample is a very effective way to detect alcohol and drug concentrations. If performed within two days, blood tests can still be used to determine your level of intoxication.

Breathalyzers: These are used to measure the amount of alcohol in your breath, giving law enforcement the ability to test drinkers on the spot.

Hair analysis: For long term drug use, hair analysis is the best way to detect the chemical traces left behind. This method has the largest detection windows, allowing the identification of use for several months afterwards, but takes longer than other testing methods to return results.

Saliva tests: Designed to pick up signs of alcohol and drug use in the saliva, these kinds of tests are becoming less popular because of their limited detection ability of two days.

Urinalysis: This is a convenient and fast way to test for drug and alcohol use, and this makes it one of the most commonly used methods for law enforcement and corporations.

Depending on the purpose of the test, and the amount of time available, you may find yourself having to take one or more of these types of drug tests.

How long do drugs stay in your system?

The length of time that different kinds of drugs can be detected in your system varies a great deal based on the type of substance:

Alcohol: When you drink alcohol, it can be detected in the blood, breath, and urine for up to 12 hours.

Amphetamines: Stimulants like black beauties, reds, and speed can be detected in urine for up to two days, and in the hair for three months.

Barbiturates: The detectability of these sedatives can vary based on whether they are short or long acting. Short acting barbiturates can be detected in the system for two days, and in the urine for up to five days. Longer-acting drugs like phenobarbital can be detected in the body for up to a week, and in the urine for up to three weeks.

Benzodiazepines: Drugs such as Valium, Xanax and Atavan are called benzodiazepines, and can they be detected in your urine for up to a week after use.

Cocaine: Although signs of this stimulant will hit their peak after roughly fifteen minutes, the traces can still be detected in the blood for roughly 12 hours. A urine test will detect cocaine for up to two weeks, and hair tests can pick it up for over three months.

Heroin: Whether you're injecting, snorting, or smoking, heroin is cleared from your body quickly. A urine test can identify heroin use for up to two days.

Marijuana: The THC in marijuana is stored in fat cells in your body, allowing for a longer detection window. If you're a casual pot smoker, the THC can be detected by a urine test for up to a week. Chronic users, however, can still fail the test for up to four weeks.

Methamphetamine: The signs of meth use peak at about 12 hours, but a urine test can pick it up for as many as four days afterwards. Traces can be found in hair for several months.

Not everyone will respond to drug tests exactly the same. While it's possible to offer general guidelines about detection times, you should know that individual tests can be affected by several factors, including:

  • How much of the drug is used
  • How often you use the drug
  • Height
  • Weight
  • Gender
  • Your overall health
  • The speed of your metabolism

The single best way to pass a drug test, of course, is to stay clean in the first place.

Failing a drug test

Depending upon the organization issuing the test, the consequences of a failed drug test can range from inconvenient to devastating.

  • Termination: Many employers will simply fire you if you fail a drug test. If the test is administered as part of the hiring procedure, it can cost you the job opportunity.
  • Return to duty test: If you are given a second chance after failing a drug test, you could find that you need to pass a return to duty test as part of the process. This test can be in addition to outside requirements such as going into rehab.
  • Follow up testing: Even if you're permitted to keep your job, you may still be subject to follow up testing to make sure you aren’t continuing to abuse substances.
  • Probation: If you're on probation, the price of a failed drug test gets even higher. The violation could land you back in front of a judge, and even result in your parole being revoked, landing you in jail.

If you find yourself worrying about failing drug tests, for yourself or for someone you love, it’s a strong indicator that you need help. There are many resources available to help you, and you should probably consider researching the right rehab program for you.

When you need answers to you drug testing questions such as "How long do drugs stay in your system?", you can count on the anonymity and accuracy of the Experts on JustAnswer. The advice they provide can help you to choose your best course of action in a difficult situation.

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