The 3 Factors That Decide How Long Benzos Stay in Your System


Benzos are a commonly-prescribed class of drug, and they are also growing in popularity as recreational drugs users take to relieve anxiety or get high. If you’ve recently taken a benzo, will it cause you to fail an upcoming drug test? How long do benzos stay in your system? In this guide, we go over how soon after taking a benzo you’ll be able to pass four different types of drug tests, the half life of benzodiazepines, what affects how long benzos stay in your system, and how you can pass your drug test faster.


What Are Benzos?

Benzos is short for benzodiazepine, a class of psychotropic drugs commonly used to treat anxiety and panic disorder. They can also be used to treat seizures, insomnia, muscle twitching, and restless leg syndrome. Benzos work by reducing the activity of neurons in the brain that cause stress and anxiety.

There are more than 15 types of FDA-approved benzo drugs, and common brands of benzos include Xanax, Klonopin, Ativan, and Valium. Xanax is the most commonly prescribed benzo. Some people take benzos recreationally for the calming effect they produce and as a way to get a relaxed “high” feeling.


How Long Do Benzos Stay in Your System?

How long do benzos stay in your system? That will depend somewhat on which benzo you take, but most of them last roughly the same amount of time. You’ll begin to feel the effects of the benzo about 15 minutes to an hour after you take it, with peak effects occurring around two to four hours after taking the drug. Effects last about four to eight hours for most benzos. The half life of benzodiazepines ranges from about 5 hours to 100 hours, with the average benzodiazepine half life between 10 and 20 hours.

In the chart below, you can see how long, on average, detectable levels of benzos remain for four different drug tests.

How Long Detectable Levels Remain
1-3 days
2-5 days
3-14 days
Up to 90 days

Most drug tests for benzos are urine tests. How long do benzos stay in your urine? Detectable levels of benzos can remain in your urine for as short a time as three days or up to about two weeks after you last took the drug.  Benzos will be removed faster from your blood and saliva than they are from urine, but they can be detected in a hair follicle test up to three months after you last took a benzo.


What Affects How Long Benzos Stay in Your System?

It’s impossible to predict exactly how long benzos will stay in your system since the answer depends on multiple variables. In this section we discuss three of the most important.


Your History of Benzo Use

The most important factor that determines how long benzos stay in your system is how often and how long you’ve been taking benzos. If you’ve used benzos heavily and for a long time, they’ll stay in your body longer compared to someone using them for the first time or who only uses them sporadically. This is because using benzos heavily causes them to build up in your body so it takes longer for them to be completely removed from your system.


The Type of Benzo You Take

As we mentioned above, the half life of benzodiazepines can vary significantly depending on which specific drug you take. Some benzos have a half life of a few hours, while others have a half life of over two days. Below is a benzodiazepine half life comparison chart so you can compare common benzodiazepine half lives.

Drug Name (Brand Names) Half Life in Hours
Alprazolam  (Xanax, Xanor, Tafil) 6-12
Bromazepam (Lexotan, Lexomil) 10-20
Clobazam (Frisium) 12-60
Clonazepam (Klonopin, Rivotril) 18-50
Diazepam (Valium) 20-100
Lorazepam (Ativan, Temesta, Tavor) 10-20
Oxazepam (Serax, Serenid, Serepax, Seresta) 5-15


Your Metabolism

Your metabolism is what determines how quickly your body processes and removes substances. The faster your metabolism is, the faster those substances, including benzos, will be removed from your body. In general, younger people have faster metabolisms compared to older people, and skinnier people have faster metabolisms compared to heavier people.


How Can You Get Benzos Out of Your System Faster?

What can you do if you’ve recently taken a benzo but need to pass a drug test? Unfortunately, the only guaranteed way to clean test results is to avoid benzos for at least three weeks before your drug test. If that isn’t possible, you may be able to remove benzos from your system slightly faster by drinking lots of water to flush the drugs out of your system. Aim to drink one to two cups of water an hour for a day or two before your drug test. This isn’t a guaranteed method, but it can help if you’re on the cusp of the passing/not passing timeline for your drug test. Doing cardio exercise for an hour or two a day a few days before your drug test can also help speed up your metabolism and remove benzos from your system faster.