How Long Does Valium (Diazepam) Stay in Your System?

Valium is a brand name for the medication diazepam, a benzodiazepine that is prescribed to treat anxiety, insomnia, seizures, muscle spasms, and alcohol withdrawal. It may also be used in combination with other sedatives to calm and sedate people before medical surgery.[1] 

Compared to other benzodiazepines, diazepam is a long-acting medication with a fairly long half-life. Depending on a number of individual factors, it can take around 10 days for Valium to leave your system, but it may be detected on standard drug tests for even longer.

How Long Do the Effects of Valium Last?

Like other benzodiazepines, Valium works by enhancing the activity of Gamma-aminobutyric acid (GABA), a naturally occurring amino acid that plays a role in central nervous system activity, emotion, thought, memory, and automatic bodily functions such as respiration.[2] The medication acts as a sedative and can make people feel calm, tired, or relaxed.

Valium is usually taken by mouth, but it can also be given via injection. When injected, the effects take place within one to five minutes and can last for several hours. When taken by mouth, the effects usually begin within 15 minutes to one hour and can last for six or more hours.

Even after the effects wear off, some of the medication will remain in your system.

What is the Half-Life of Valium (Diazepam)?

The elimination half-life is a quantitative measurement that is used to describe how long it takes 50% of a substance to leave the system. The half-life of a substance can help people determine how long it will take a drug or leave their system.

Valium has a longer elimination half-life than many other benzodiazepines. Its half-life, depending on a number of factors, can be anywhere from 30 to 56 hours. For most people, the half-life ends up being about 48 hours.[3]

It takes about five half-lives for a substance to leave your system entirely, meaning Valium can stay in your body for 10 days or more.

Having too much diazepam in your body at one time can lead to serious side effects including confusion, impaired movements and coordination, shortness of breath, and unresponsiveness. In extremely high doses, a life-threatening overdose can occur. As a result, it’s vital to only take the medication as directed by your doctor.

Factors that Influence How Long Valium Stays in your System

Diazepam’s half-life can vary from one person to the next depending on your metabolism and other factors. This means the drug can stay in one person’s system longer than another person’s, causing exact detection times to vary. 

Key factors that influence how long drugs stay in your body include:

• Age
• Weight
• Metabolism
• BMI
• Amount of the drug consumed
• Frequency of drug use
• Polysubstance abuse
• Liver health
• Kidney health
• Method if ingestion

How Long Valium Can be Detected in Urine, Blood, Saliva, and Hair

As Valium is metabolized and processed by your body, it is broken down into metabolites that remain detectable in your system for much longer than the medication itself. The drug tests screen for these metabolites. 

The most prominent Valium metabolites are nordiazepam, temazepam, and oxazepam. Some of these metabolites, including nordiazepam, have an even longer half-life than diazepam.[4] As a result, even though Valium may leave your system after 10 days, it can be detected in your body by drug tests for much longer.

Valium in Urine

The most popular type of drug test is a urinalysis test that screens urine for addictive substances. Urine tests are minimally invasive, affordable, and accurate. Valium can be detected in your urine for one to six weeks after your last dose.

Valium in Blood

Blood tests are used less often than other types of tests because they are invasive in nature and have a very short detection window. Valium is only traceable in your blood for six to 48 hours after your last dose.

Valium in Saliva

Saliva tests are sometimes used as an alternative to urine tests, but they have a shorter detection window. Valium can stay in your saliva for one to 10 days after your last dose.

Valium in Hair

Hair follicle drug testing has the longest detection window of all. Like other substances, Valium can be detected in the hair follicle for up to 90 days after your last dose.

Help for Valium Abuse and Addiction

Diazepam is a Schedule IV controlled substance that carries a risk of dependence and addiction.[5] If you have been taking the drug for more than two weeks and stop taking it suddenly, you may experience uncomfortable and potentially severe withdrawal symptoms. Since Valium is so long-acting, these symptoms may not appear for a couple of days after your last dose.

If you or a loved one are struggling with Valium addiction, our team at Mandala Healing Center is here to help. Our world-class medical detox facility can help you taper off benzodiazepines slowly, avoiding the more severe withdrawal symptoms. We’ll ensure your experience is safe, supportive, and comfortable.

Don’t wait any longer for the help you need and deserve. Call now to speak with a qualified admissions coordinator.

References:

1. https://www.accessdata.fda.gov/drugsatfda_docs/label/2016/013263s094lbl.pdf
2. https://pubmed.ncbi.nlm.nih.gov/6147796/
3. https://www.ncbi.nlm.nih.gov/pmc/articles/PMC3990949/
4. https://academic.oup.com/jat/article/38/3/135/797163
5. https://www.deadiversion.usdoj.gov/schedules/

Learn more about Valium addiction treatment.

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Clinically Reviewed

Mandala Clinical Team

This page was prepared by Mandala Healing Center and reviewed by our clinical team, the licensed medical and behavioral health professionals who provide detox and treatment at our West Palm Beach facility. We review it regularly so it reflects current clinical guidance.

Last reviewed: June 4, 2026

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Content on this page is written and reviewed according to our editorial policy. It is for informational purposes only and is not a substitute for professional medical advice. If you have questions about your medication, talk to your prescriber before making any changes.