How Long Does Valium Last?

Several 5mg/ml vials of Valium (Diazepam)

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What is the most important information I should know about Valium (diazepam)?

  • Valium can be habit-forming, even when it is taken as prescribed.
  • You should never stop taking Valium without talking to your doctor first, as it can cause serious withdrawal symptoms.

Valium (diazepam) is a fast-acting, long-lasting benzodiazepine that is often prescribed to treat anxiety disorders. How long Valium lasts depends on a variety of factors, but it can be detected in the body for up to 90 days, depending on the sample tested. Typically, you'll feel its effects from one minute to one hour after administration, depending on the route.

Since being approved by the FDA in 1963, Valium has been prescribed for a range of medical conditions including muscle spasms, seizure disorders, restless leg syndrome, insomnia, and symptoms of alcohol withdrawal.

Benzodiazepines such as Valium were originally developed to replace more dangerous and addictive barbiturates. However, these substances can still lead to physical dependence and addiction even when taken exactly as prescribed. Benzodiazepines like Valium are classified as Schedule IV controlled substances.

Valium can also have potentially dangerous interactions with other medications and substances, so knowing how long its effects last and how long it stays in your body can help minimize the risk of interaction side effects and accidental overdose.

How Long Does Valium Stay in Your System?

Urine: Up to six weeks

Blood: Up to 48 hours

Saliva: Up to 10 days

Hair: Up to 90 days

How Long Does It Take to Feel Effects?

Valium works by facilitating the activity of the chemical GABA at various receptor sites in the brain. GABA reduces activity in different areas of the brain, including regions that help control emotion, thought, memory, and automatic functions such as breathing. By increasing the effects of this brain chemical, Valium helps reduce anxiety, relax muscles, and increase drowsiness.

Valium can be taken by mouth, injection, or rectal gel. When administered via injection, valium takes just one to five minutes for the effects to kick in. When taken orally, people usually begin to feel the effects 15 to 60 minutes after ingestion. Rectal gel may be used for those who are experiencing seizures and begins working quickly after administration.

If you take Valium, it's important to know how long the drug stays active in your system to avoid associated risks.

  • Having too much Valium in your body at one time can cause serious side effects. These include drowsiness, confusion, impaired movements and balance, shortness of breath, and potentially unresponsiveness.
  • Valium can easily become habit-forming. After a period of time, you can develop a tolerance for the drug. As a result, you may have to take larger dosages. Notably, overuse of Valium can have some alarming consequences. Studies have found, for instance, that long-term use of Valium and similar drugs used to treat anxiety are associated with an increased risk of developing Alzheimer's.
  • Valium can have serious or even life-threatening side effects if you take certain other medications before it's totally cleared from your body. It's especially dangerous to take sedatives, sleeping pills, or tranquilizers if you have Valium in your system. The same is true of drinking alcohol.

How Long Do Valium's Effects Last?

Valium has a half-life of approximately 48 hours. The half-life of a drug is how long it takes for half of a dose to be eliminated from the body.

Valium levels typically peak in the bloodstream in about one to two hours. While the physiological effects may only last between four to six hours, the drug will be detectable in the body for much longer.

A 5mg dose of Valium, therefore, might have a half-life of around 50 hours, but small amounts may remain in the body for up to 90 days, depending on the testing method.

As Valium is processed by the body, it is broken down into other substances known as metabolites. In many cases, these metabolites are detectable in the body for much longer than the drug itself. The most common metabolites of Valium are nordiazepam, temazepam, and oxazepam.

The metabolites of the drug may have much longer half-lives as well. Nordiazepam, for example, has a half-life of up to 100 hours. Valium also accumulates when people take multiple doses over a period of time, which can slightly prolong the total half-life of the substance.

Valium—or rather, metabolites associated with the medication—can be detected in the body in different ways.


Valium can be detected in urine for one to six weeks after being taken.


Valium is detectable in blood for six to 48 hours. Blood tests tend to be used less frequently than other test methods due to the shorter detection window and the more invasive nature of the test. However, a blood test may be used in some forensic settings or to confirm an unexpected positive urine test result.


A saliva test can detect Valium for one to 10 days after it's taken. Research suggests that saliva testing can be a viable alternative to urine testing for the detection of Valium and other benzodiazepines.

While saliva tests have a fairly long detection window, this type of testing can present some challenges. Valium side effects can include dry mouth or hypersalivation, which can affect the ability to collect an adequate sample or may dilute the amount of detectable substance in the oral fluid.


Like many other drugs, Valium can be detected with a hair follicle drug test for up to 90 days. The long detection window of this testing method means that it can be used to look for past drug use. If you have been prescribed Valium to treat anxiety or another condition, be sure to inform the testing lab, even if you are no longer taking your medication.

False Positive Testing

There are some medications that may cross-react with drug screens. There are reports of the antidepressant medication Zoloft (sertraline) and prescription non-steroidal anti-inflammatory drug Daypro (oxaprozin) causing false-positive urine screens for benzodiazepines like Valium.

Always disclose any prescription or over-the-counter medications you are taking to the lab so clinicians can accurately interpret your drug screen results.

Factors That Affect Detection Time

There are many variables that affect how long Valium remains in the body. The rate at which medications and other substances break down depends on things like metabolism, age, weight, percentage of body fat, activity level, and hydration. Some health conditions, including liver impairments, can play a role in the rate at which drugs are metabolized by the body.

Other factors that can affect how long Valium stays in the body have to do with the specific prescription. The larger the dose and more frequently you take it, for example, means it will likely remain in your body for longer.

Why You Might Be Tested

Some prospective employers order drug tests during the interviewing process to screen for possible drug misuse. Or, a doctor may want to make sure you don't have traces of Valium in your system before prescribing another medication. Understanding how long Valium remains in your body can help you avoid potentially serious drug interactions.

How to Get Valium Out of Your System

While the effects of diazepam will begin to wear off after about six hours, it will take much longer for this long-acting benzodiazepine to fully clear your system. You may want to get Valium out of your system if you are experiencing unpleasant side effects or if your doctor is planning to switch you to another medication.

The first step to getting Valium out of your system is to stop taking the drug. However, you should never stop taking prescribed medication without talking to your doctor first. Your doctor may recommend gradually tapering your medication to avoid withdrawal symptoms.

Because your body can develop a tolerance and dependence on the substance, suddenly stopping your medication can decrease your body's tolerance for the drug.

If you start taking it again at the same dose, it can result in an accidental overdose. Discuss your options for safely stopping your medication, which may involve a gradual reduction in your dose in order to avoid withdrawal effects, a process known as tapering.

Once you have safely stopped taking Valium, make sure that you stay well hydrated, eat a healthy diet, and get regular physical exercise. Such habits may help to slightly increase how quickly your body metabolizes and excretes the drug and its metabolites.

Symptoms of Overdose

Benzodiazepines such as Valium are usually considered safe when they are taken as prescribed. However, there are a number of factors that can increase the risk of overdose.

These include taking Valium in combination with other central nervous system depressants or alcohol, taking more than your prescribed dose, or taking the drug more frequently than prescribed. Being aware of the signs of a Valium overdose is important so that you or a loved one can get help as quickly as possible. Some signs of a potential Valium overdose include:

  • Very deep sleep
  • Blue lips
  • Mental confusion
  • Dizziness
  • Lack of coordination
  • Blurry vision
  • Weakness
  • Difficulty breathing
  • Unresponsiveness

If someone is experiencing these symptoms, contact emergency services right away.

Getting Help

Valium carries a risk of dependence. If you suddenly stop using Valium, you may experience symptoms of benzodiazepine withdrawal, which can include anxiety, nausea, seizures, insomnia, tremors, and mental changes including confusion and even psychosis. With longer-acting drugs like Valium, withdrawal symptoms may not appear for a few days after your last dose.

If you believe that you might have a physical dependence or addiction to Valium, talk to your doctor. Your doctor can offer advice and assistance. In some cases, you might want to seek help from a medical detox center, since benzodiazepine withdrawal symptoms can be severe. 

Treatment options for Valium use disorders may take place in inpatient or outpatient treatment centers and involve individual psychotherapy or support groups to aid in your long-term recovery. Effective treatments may involve tapering your dosage to manage withdrawal symptoms as well as psychotherapeutic approaches including cognitive-behavioral therapy and contingency management.

If you or a loved one are struggling with substance use or addiction, contact the Substance Abuse and Mental Health Services Administration (SAMHSA) National Helpline at 1-800-662-4357 for information on support and treatment facilities in your area. 

For more mental health resources, see our National Helpline Database.

6 Sources
Verywell Mind uses only high-quality sources, including peer-reviewed studies, to support the facts within our articles. Read our editorial process to learn more about how we fact-check and keep our content accurate, reliable, and trustworthy.
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  4. Dhaliwal JS, Rosani A, Saadabadi A. Diazepam. In: StatPearls [Internet]. Treasure Island (FL): StatPearls Publishing; 2022.

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Additional Reading

By Buddy T
Buddy T is an anonymous writer and founding member of the Online Al-Anon Outreach Committee with decades of experience writing about alcoholism.