Free & Confidential Drug Hotline. Call NOW:

How Long Do Benzos Stay In Your System: MOA and Drug Testing

Last Updated: June 13, 2022

Authored by Sharon Levy, MD, MPH

Reviewed by Tania Kelly

Benzodiazepines are central nervous depressants that are prescribed to treat anxiety, seizures, panic attacks, alcohol withdrawal and for inducing anesthesia. They are also used as muscle relaxants and to treat sleep issues and insomnia. Despite its potential benefits, failure to understand benzodiazepines mechanism of action or ignoring drug interactions can seriously endanger a patient’s life, with a high potential for benzo overdose leading to death. Based on figures revealed by the National Institute on Drug Abuse, about a third of all cases of opioid overdose also involve benzos. The time for which benzos stay in one’s system depends on the half-life of benzos and several other factors, as there are short acting benzodiazepines and long acting benzodiazepines.

Drug Testing: How Many Days Do Benzos Stay in Your System?

Benzodiazepines can be detected in the urine, blood, saliva, and hair samples of an individual during drug testing. Answering the question of how long do benzos stay in your system, one should notice that the detection time varies depending on the type of benzo being tested and the medium in which it is being tested. The average detection times of different benzos in various mediums are further described in the following sections.

How Long Do Benzos Stay In The Urine?

How long benzos stay in urine depends on their half-life. After it is metabolized by the body, about 1/5th of the medicine stays in one’s urine for some time. The detection time may vary depending on the medicine or its metabolite in the urine sample. For slow-acting benzos, the detection time is approximately two days. For intermediate-acting benzos, the drug test will be able to detect the drug for up to 5 days. A benzo urine drug test will be able to detect long acting benzodiazepines for up to 10 days after discontinuing the drug. A standard benzodiazepine urine test may not be able to detect every benzo or its metabolite. For such benzodiazepines, a urine drug test will be inconclusive, and other conclusive tests may be required for confirmation.

How Long Do Benzos Stay In The Blood?

The time for which benzodiazepines or their metabolites stay in the blood is relatively shorter than how long benzos stay in urine. Benzodiazepines can be detected in the blood within hours of its intake. However, the detection window in the blood is quite small. A blood test will only be able to detect benzos for 24 hours.

How Long Does Benzodiazepine Stay in The Saliva?

A saliva test will be able to detect benzodiazepine in the saliva of an individual for up to 2 and a half days after its intake. This makes the detection window of saliva more than blood but less than urine. Saliva drug tests are relatively expensive and less common than blood, urine, or hair drug testing.

How Long Does Benzodiazepine Stay in The Hair?

Benzos can be detected in hair samples of individuals. In fact, the detection window of benzodiazepines in a hair sample is the greatest. A hair drug test will be able to detect benzos for up to 90 days after their intake. However, a hair drug test will not be able to detect benzodiazepine until after a few days of ingestion. The drug gets accumulated in the outgrowths of hair follicles, so a few days’ time is required for the drug to show up on the length of the hair. A hair drug test will be able to detect long-acting benzos with more accuracy than a short-acting benzodiazepine.

Benzos drug testing results.

Do All Benzodiazepines Show Up The Same On A Drug Test?

No, all benzodiazepines show differently on drug tests. Short acting benzodiazepines have a shorter half-life and are eliminated from the body much faster. These include benzos such as Xanax, Serax, Halcion, and Restoril. Hence, these benzos will only be able to be detected for a few hours after they are administered. Intermediate-acting benzodiazepines can be detected for longer durations in any kind of drug test as compared to shorter-acting benzos. They include Doral, Klonopin, and Mogadon. The long acting benzodiazepines will be detected for longer duration as compared to the short and intermediate-acting ones. Drugs such as Valium, Librium, and Tranxene are included in this category.

What Can Cause A False Positive Drug Test Benzodiazepines?

Certain factors can cause a false positive drug test for benzodiazepine. These include the use of Sertraline, a Selective Serotonin Reuptake Inhibitor (SSRI), and Oxaprozin, a non-steroidal anti-inflammatory drug (NSAID). According to this study about false-positive urine screening for benzodiazepines, it was concluded that a false positive drug test benzodiazepines was caused when Sertraline was used. The study results were cross-referenced to check if the individuals with a false positive benzodiazepine test were also prescribed Sertraline during that time. It was concluded that those individuals did, in fact, have an active Sertraline prescription.

Benzodiazepines Half Life

Benzodiazepine drugs comprise several types of drugs with their mechanism of action and the types of disorders they treat. According to the study about the pharmacokinetic properties of benzos, the time drugs stay in the system and benzodiazepines half life is different and depends on its different types. Benzodiazepines can be classified into three categories, each having its own average half-life duration.

  • Short Acting Benzodiazepines Half-Life– Short acting benzodiazepines half-life is within 1 to 12 hours on average. These include Tranxene, Versed, Halcion, and others. Their duration of action is roughly between 3 to 8 hours, with a peak level achieved around 1-2 hours.
  • Intermediate-Acting Benzos Half-Life– They include medicines such as Xanax, Ativan, Prosom, and Restoril. Intermediate-acting benzos half-life is 12-40 hours on average with peak level achieved around 2 hours after administration.
  • Long Acting Benzodiazepines Half-Life– The long acting benzodiazepines have an average half-life of more than 40 hours, even up to 250 hours, in some cases. Long-acting benzos include Valium, Librium, Dalmane, and others.

Factors That Influence How Long Benzos Stay In The System

Several factors affect the process of benzodiazepines elimination from the body. Some of these are general factors, whereas others are individual factors that vary from person to person. These are described in detail below:

  • Half-Life Of The Particular Drug– The main factor which determines how long benzos stay in a body system is the half-life of the particular drug being taken. Short-acting benzos will be eliminated from the body in a lesser amount of time as compared to long-acting benzo.
  • Amount Of Benzos Taken– The dosage of the drug also affects the time it will take to eliminate it from the body. A higher dose will take more time for it to be excreted from the body as compared to a lower dose.
  • Frequency Of Use– The frequency with which benzo is taken will affect the time it will take to eliminate it from the system. If taken for the long-term, it will take more time for the drug to stay in the system as compared to if it were taken for the short-term.
  • Interactions With Other Drugs– When benzos are taken in combination with other drugs or alcohol, it will take a longer time to eliminate from the system.
  • Age And Weight of Patient– Individual factors such as the age, weight, and height of a person also affect the duration for how long benzos stay in a body system. These factors affect the rate of metabolism, which, in turn, affects the time any drug stays in the system.
  • Individual Metabolic Rate– The metabolic rate of each individual determines the time it will take the body to digest and eliminate drugs from the system. People with a high metabolic rate will be able to rid their body off benzos faster than the ones with slower metabolic rates.
  • Benzodiazepines Metabolism Process– The metabolism process of benzodiazepines effects how long benzos stay in the system. The process varies with the type of medications in question. The general metabolism process of a benzodiazepine starts when it is ingested. After that, it is broken down by the liver into different chemical components called metabolites. Almost all metabolites of benzos created in this process are pharmacologically active with long half-lives. These metabolites can also be detected in BZD drug tests. The metabolites are mainly excreted by the kidneys.

Benzodiazepines Mechanism of Action

Benzodiazepines belong to a category of drugs known as CNS (central nervous system) depressants. Benzodiazepines mechanism of action is inhibitory. That means they slow down the activity of neurons located in the central nervous system. So how do benzodiazepines work?

Benzodiazepines mechanism of action work by the following:

  • First, benzos target the GABA-A (gamma-aminobutyric acid) receptors. GABA-A receptors function by inhibiting synapses that enable movement, anxiety, and other active brain activities.
  • Second, benzodiazepines improve the binding of GABA to GABA-A receptors, thereby enhancing the inhibitory effect of GABA.
  • Third, they help open up chloride channels, permitting more chloride ions to enter the neuron. As a result, the neuron becomes less responsive to becoming excited.

Benzodiazepine structure is characterized to be a combination of a benzene ring and a diazepine ring. It is consistent across different types, and all deliver their therapeutic benefits by increasing GABA receptor activity, which, in turn, inhibits neuron function. This results in a calming effect.

Benzodiazepines Detox And Getting Drugs Out Of The System Safely

Based on the benzodiazepines mechanism of action, benzos can be beneficial in many ways if taken with care. However, patients should consult health professionals on how to safely get benzodiazepines out of the system. Such methods may include hydration, nutritional support and physical exercise to boost metabolism.

Benzos are powerful medications that can be addictive and the side effects of benzodiazepines can be quite annoying. This may be more likely if a patient takes it inappropriately or for a long time. It is critical to talk to an addiction counselor at a benzodiazepine rehab facility. They can teach ways to deal with the cravings, prevent relapses, since abrupt benzodiazepines withdrawal may be risky, dangerous to health, and possibly lead to life-threatening conditions. Finally, the addict will be on their way to a full recovery.

Hope Without Commitment

Find the best treatment options. Call our free and confidential helpline

Most private insurances accepted

Marketing fee may apply

Page Sources

  1. Buffett-Jerrott, S. E., & Stewart, S. H. (2002). Cognitive and sedative effects of benzodiazepine use. Current pharmaceutical design, 8(1), 45–58. https://doi.org/10.2174/1381612023396654
  2. European Monitoring Centre for Drugs and Drug Addiction (EMCDDA). (n.d.). Benzodiazepines drug profile. https://www.emcdda.europa.eu/publications/drug-profiles/benzodiazepines_en
  3. Greenblatt, D. J., Shader, R. I., Divoll, M., & Harmatz, J. S. (1981). Benzodiazepines: a summary of pharmacokinetic properties. British journal of clinical pharmacology, 11 Suppl 1(Suppl 1), 11S–16S. https://doi.org/10.1111/j.1365-2125.1981.tb01833.x
  4. Griffin, C. E., 3rd, Kaye, A. M., Bueno, F. R., & Kaye, A. D. (2013). Benzodiazepine pharmacology and central nervous system-mediated effects. The Ochsner journal, 13(2), 214–223. https://www.ncbi.nlm.nih.gov/pmc/articles/PMC3684331/
  5. National Institute on Drug Abuse (2022, April 21). Benzodiazepines and opioids. Retrieved from https://nida.nih.gov/research-topics/opioids/benzodiazepines-opioids
  6. Nasky, K. M., Cowan, G. L., & Knittel, D. R. (2009). False-Positive Urine Screening for Benzodiazepines: An Association with Sertraline?: A Two-year Retrospective Chart Analysis. Psychiatry (Edgmont (Pa. : Township)), 6(7), 36–39. https://www.ncbi.nlm.nih.gov/pmc/articles/PMC2728940/
  7. University of Rochester Medical Center. (n.d.). Benzodiazepines (Urine). University of Rochester Medical Center Health Encyclopedia. https://www.urmc.rochester.edu/encyclopedia/content.aspx?contenttypeid=167&contentid=benzodiazepine_urine

Published on: December 5th, 2019

Updated on: June 13th, 2022

About Author

Sharon Levy, MD, MPH

After successful graduation from Boston University, MA, Sharon gained a Master’s degree in Public Health. Since then, Sharon devoted herself entirely to the medical niche. Sharon Levy is also a certified addiction recovery coach.

Medically Reviewed by

Tania Kelly

Tania Kelly, author of Keep Calm and Treat Addiction is a credentialed Mental Health Nurse and Tobacco Treatment Specialist, passionate about addiction recovery. As a senior clinician, Tania constantly shares the concepts outlined in her book with health service providers, aiming to demystify addiction treatment and equip others in evidence-based practice.