How Long Does Klonopin Stay in Your System?

Klonopin (Clonazepam) is a medication that is used to control seizures or relieve panic attacks. This medication is used to help control a person’s condition, but not cure it. It works by decreasing the abnormal electrical activity in a person’s brain.

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A person may experience side effects such as drowsiness, dizziness, unsteadiness, problems with coordination, difficultly remembering or thinking, increased saliva, muscle or joint pain, blurred vision, or frequent urination when taking this medication. More serious side effects that require immediate medical attention include rash, hives, swelling of the face, eyes, tongue, lips, and throat, difficulty breathing or swallowing, and hoarseness.

Klonopin Addiction

Klonopin is a long-acting and high potency benzodiazepine. Benzodiazepines are addictive and suddenly stopping Klonopin without talking to your doctor can result in withdrawal symptoms such as new or worsening seizures, hallucinations, changes in behavior, sweating, uncontrollable shaking of a part of your body, stomach or muscle cramps, anxiety, or difficulty falling asleep or staying asleep.

Abuse of Klonopin can result in addiction and dependence. When attempting to come off this medication your doctor will probably recommend a gradual decrease in your dose, known as a slow taper, to prevent these withdrawal symptoms. Abruptly stopping this medication can be dangerous or even life-threatening.

How Long Does Klonopin Stay In System?

How long does Klonopin last? Klonopin’s half-life is around 30 to 40 hours or about 1 and a half days. This means that it will take between 30 to 40 hours for half the drug to leave your body. It takes around 5 to 7 half-lives to clear 98 percent of a drug dose out of your system.

Klonopin Drug Tests

Klonopin drug test detection time depends on the particular drug test used. There are a few different drug tests that a person can take to determine if they are using Klonopin. These include urine tests, hair tests, oral fluids, and blood tests.

Urine Test

A urine drug test analyzes your urine for the presence of certain illegal drugs and prescription medication. Urine is the most preferred drug test due to its easy collection. Also, urine tends to have a higher concentration of drugs and their metabolites, which allows longer detection times.

How long is Klonopin detectable in urine? Klonopin is a long-acting benzodiazepine. This means that it stays longer in a person’s system. The length of time that Klonopin is detectable in urine is about 5 days, although it is detected for up to 30 days. Klonopin is detected in urine as the metabolite 7-aminoclonazepam.

Hair Test

Hair tests require a sample of hair from a person to be tested for drugs. The advantages of taking a hair sample are that it provides the longest window of detection of a substance. Hair samples may be able to detect changes in drug use over time. Klonopin can be detected in hair as early as 3 days after taking the drug and for up to 28 days.

Oral Fluids

Oral fluid collection is another form of drug test. In this test, a swab is taken in the mouth to collect saliva that will be tested for drugs. In saliva, drugs can appear within minutes of drug administration. The advantages of this test are that it is noninvasive, easy to collect, low chance of adulteration, the specimen collection can be directly observed, and can detect same-day use of some drugs. Klonopin can be detected in oral fluids for 7 to 9 days.

Blood Test

A blood test is done with a blood sample that uses a needle to draw blood from a vein in your arm or hand. In older adults or people who suffer from liver disease, certain benzodiazepines can last longer in the blood. Klonopin can show up in blood 1 to 2 hours after a person takes the drug. It can be detected in a person’s blood for several days.

Does Klonopin show up in a drug test?

Whether or not Klonopin can be detected through these drug tests depends on the sensitivity of the test. Urine tests have a cutoff level, meaning that if the concentration of 7-aminoclonazepam in urine is below the cutoff level the test will come back negative.

Additionally, one interesting finding is that urine tests have difficulty distinguishing between individual benzodiazepines. This means that the specific drug Klonopin might not show up on a drug test, but its broader drug category, benzodiazepine will.

Factors That Impact Detection Time

Drug detection time is the amount of time that has passed since you last took a drug, that drug testing can determine the drug’s presence or metabolites in your sample. How long does Klonopin stay in your system? The length of time Klonopin will stay in your system depends on a lot of different factors. These include hydration, dosing, age, race, kidney function, metabolic rate, body mass, urine pH, and frequency of use.


Hydration is a factor because the more diluted a person’s urine is the more diluted the drug will appear in urine resulting in a negative result due to levels present being below the cutoff.


Dosing is another factor because if a patient is on a low dose, then they will also have low amounts of the drug in their urine, which might be too low to be detected.

Age & Race

Age and race are factors because the younger a person is the better their body can metabolize drugs. In general, elderly people tend to eliminate the drug much more slowly.

Kidney Function

Kidney function plays a role in how long drugs stay in your system because people who have kidney failure take longer to metabolize drugs.

Rate of Metabolism

The rate of metabolism is another factor because every person has a different rate of metabolism which is determined by their genetics such as age, sex, ethnicity, and liver impairment, and environment. The faster someone can metabolize and break down the drug, the quicker it can leave their system. According to a study published in American Family Physician, genetic factors account for 20 to 95 percent of patient variability in response to individual drugs.

Body Mass

Body mass is another factor because fatty tissues tend to store chemicals longer than lean tissue. Drug detection times can be much longer for people who have more fatty tissue because their drug metabolites tend to accumulate in those tissues.

Urine pH

Urine pH can also impact Klonopin detection time. The more acidic a person’s urine is the shorter their detection time will be.

Frequency of Use

Lastly, the frequency of use plays a role in determining how long Klonopin stays in a person’s system. For example, a person who is on a high dose of a drug will take longer to get the drug out of their system than someone on a low dose. If someone has built up a tolerance to the drug it tends to metabolize quicker. This means that the length of time it can be detected in their system is shorter. On the other hand, a first-time user of Klonopin might be detectable in a drug test for only a short time.

Final Thoughts

There are many reasons why a person might have to have a drug test. These include pre-employment screening, probation, legal cases, custody, court-ordered testing, and more. No matter your reason for needing a drug test it can be stressful if you know you are addicted to drugs and will most likely fail the drug test.

If you or a loved one is suffering from a Klonopin addiction, finding a high-quality rehabilitation center can help. An active rehabilitation approach can best treat someone wishing to overcome their substance use disorder problem. An active rehabilitation approach combines entry into a substance use disorder treatment center with support, education, and lifestyle changes.


Medical disclaimer:

Sunshine Behavioral Health strives to help people who are facing substance abuse, addiction, mental health disorders, or a combination of these conditions. It does this by providing compassionate care and evidence-based content that addresses health, treatment, and recovery.

Licensed medical professionals review material we publish on our site. The material is not a substitute for qualified medical diagnoses, treatment, or advice. It should not be used to replace the suggestions of your personal physician or other health care professionals.

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