Article at a Glance:
- Benzos are common drugs taken by millions of Americans.
- They can stay in your system for varying lengths of time, depending on the benzo.
- Rough estimates of how long benzos stay in your system depend on the drug, but in general:
Table of Contents
How Benzos Affect the Brain and Body
Benzodiazepines affect the GABA receptors in the brain and spinal cord. When administered, they bind with the GABA receptors and make it more difficult for excitability to occur inside the brain, which is what causes the tranquilizing and anti-anxiety effects of the drug.
The issue with long-term or excessive benzo use is that benzodiazepines can cause a depletion of GABA receptors. This can ultimately have a reverse effect on the brain, making someone more likely to experience hyper-excitability. This can lead to insomnia, heightened anxiety and other symptoms of chronic abuse. This results in a cyclical effect, where people develop a tolerance, begin taking more which increases their tolerance, often without realizing they’ve become addicted.
People who have become addicted to benzos often want to know how long it takes for the drugs to be removed from the system.
Benzodiazepines Showing up on Drug Tests
Like most drugs, benzodiazepines can show up on a drug test. Most major drug tests screen for benzodiazepines. Benzos can be detected for different lengths of time, depending on both the benzo and what is being tested.
How Long Do Benzos Stay in Your Urine, Hair, Saliva and Blood?
Benzos can be detected in standard drug tests including those that examine urine, hair, saliva and blood tests. The specific amount of time the benzo can be found in your system depends on the exact drug. Some rough estimates for detection times are:
- Urine: Anywhere from 1–10 days,
- Hair: A half-inch hair sample can detect benzos for up to 90 days
- Saliva: Up to two days
- Blood: Anywhere from one hour to eight days
Peak Levels and Benzodiazepine Half-Life
When looking at how benzos affect the body, we look at peak level and half-life. Peak level is the highest concentration of a drug in the person’s bloodstream, whereas the half-life of a drug refers to how long it takes for the body to get rid of half of the dose. In general, it takes five half lives before a drug is completely cleared from your system.
Peak levels and drug half-life of benzodiazepines depend on several factors, such as the specific drug that has been prescribed or ingested, dosage amount and method of administration. In general, for benzos that are taken by mouth, the peak times and half-lives are:
|Benzodiazepine||Time to peak level||Half-life|
|Alprazolam||1-2 hours||12-15 hours|
|Chlordiazepoxide||Several hours||24-48 hours|
|Clonazepam||1-4 hours||18-50 hours|
|Diazepam||0.5-6 hours||20-80 hours|
|Lorazepam||1-2 hours||10-20 hours|
|Oxazepam||3 hours||5-11 hours|
Factors That Influence How Long Benzos Stay in Your System
Several factors play a role in how long benzodiazepines stay in your system. The most influential factors to consider are:
- Age: The older a person is, the longer a benzo tends to last in their system.
- Kidney function: Certain benzos, particularly chlordiazepoxide and lorazepam, may last longer in your system if you have kidney problems.
- Liver function: Some benzos, like chlordiazepoxide, diazepam and lorazepam, may last much longer in your system if you have liver problems.
- Benzo dose: The higher the dose, the longer it can take your body to eliminate a benzo.
- Frequency of use: Depending on how long someone has been taking benzos and at what level, the process of clearance varies. If a person only takes a single dose, they will eliminate it from their system much faster than a person who uses it on a regular basis.
Benzodiazepines Prescription Facts
Millions of benzo prescriptions are filled every year. About 12.5% of U.S. adults have used benzodiazepines at some point. Among these, about 17.1% of benzodiazepine users have misused the benzo, and under 2% meet the criteria for benzodiazepine use disorder. The most commonly prescribed benzos are clonazepam, lorazepam and diazepam.
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- 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.