How Long Does Valium Stay in Your System?

handful of Valium next to image depicting body scan

Valium, a brand name for diazepam, is a medication commonly prescribed to treat anxiety, sleep disorders, panic attacks and seizures. Valium works by suppressing brain activity, resulting in relaxation and drowsiness. Although Valium is a valuable treatment for several health conditions, Valium misuse frequently occurs and can lead to physical dependence and addiction. Whether an individual is using Valium with a prescription or illicitly, it is essential to understand how long Valium stays in your system and factors that impact its clearance from the body.

Duration of Valium’s Effects

How long the effects of Valium last depend on the dose, administration route, frequency of use and individual biological factors. When taken orally, more than 90% of Valium is absorbed and the average time to achieve peak concentrations within the body is 1 to 1.5 hours. Therapeutic doses of Valium result in immediate effects within 30 minutes, while significant effects can last for 12 to 24 hours. Higher doses or injected Valium can result in effects within just a few minutes that last several days.

Valium Half-Life

Valium’s half-life indicates how long it takes for 50% of a drug dose to be removed from the body. The average diazepam half-life is approximately 43 hours, meaning that about 50% of the drug will be cleared from the body after about 43 hours. Thus, it may take up to 10 days to eliminate Valium from the body. Valium is broken down into several metabolites. One such metabolite, nordiazepam, has a much longer half-life and can thus be detected for a longer period. The average half-life of nordiazepam is 40 to 99 hours, indicating that it can take over 20 days to eliminate Valium byproducts from the body.

Valium Detection Times

Valium drug tests generally rely on the detection of diazepam or its metabolites. How long Valium shows on drug tests depends on the dose, the length of use and the exact laboratory test utilized.


How long does Valium stay in your urine? Urine tests can sense the existence of Valium for several days or weeks after the last use.


How long does Valium stay in your blood? When taken orally, blood tests can detect Valium for one hour after injection, on average. Injected Valium can be detected in a blood test 15 minutes after dosing.


How long does Valium stay in your saliva? Valium saliva tests can detect the drug for seven to nine days after administration.

Factors Affecting How Long Valium Stays in Your System

Many factors impact the clearance of Valium from the body, including:

  • Amount used: The dose of Valium influences how long the drug can be measured in bodily fluids. Larger does require longer to break down and be excreted from the body.
  • Frequency of use: When Valium is taken repeatedly over a prolonged time frame, it takes longer for the body to process and fully clear the drug.
  • Method of use: How Valium is administered impacts how long the drug stays within the body. Oral Valium may take longer to metabolize compared to injected Valium, although this depends on the dosage.
  • Age: Age-dependent biological factors impact the clearance of Valium from the body. Elderly patients and infants generally have a longer Valium half-life.
  • Overall Health: An individual’s overall health can alter Valium uptake and clearance. For example, individuals with obesity or chronic diseases may take longer to break down and eliminate Valium.
  • Liver Function: The liver plays an essential role in processing and eliminating Valium from the body, so individual variations in liver function alter how long Valium is detected in drug screening tests.

False Positives for Valium

In rare situations, a false positive for Valium may occur during drug testing. False positives can occur when the antibodies used in testing bind to other drug components that are similar to diazepam or its metabolites. Certain medications can cause false-positive results in tests for benzodiazepines, including tolmetin, naproxen, etodolac, fenoprofen, oxaprozin and sertraline. The possibility of false-positive results should be discussed with a medical professional.

How Valium is Broken Down in the Body

The liver processes Valium using enzymes such as CYP3A4 and 2C19. Once broken down in the liver, Valium and its metabolites are mainly excreted from the body through the kidneys in urine. How fast Valium is removed depends on the dosage, as Valium accumulates in the body.

If you or a loved one live with Valium addiction, The Recovery Village Ridgefield can help. Contact us today to learn about our treatment options and begin the initial steps toward addiction recovery.

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University of Rochester Medical Center. “Benzodiazepines (Urine).” 2019. Accessed August 31, 2019.

Medical Disclaimer: The Recovery Village aims to improve the quality of life for people struggling with a substance use or mental health disorder with fact-based content about the nature of behavioral health conditions, treatment options and their related outcomes. We publish material that is researched, cited, edited and reviewed by licensed medical professionals. The information we provide is not intended to be a substitute for professional medical advice, diagnosis or treatment. It should not be used in place of the advice of your physician or other qualified healthcare provider.