Clonazepam Half-Life: How Long Does Klonopin Stay in Your System?

Klonopin (clonazepam) is a benzodiazepine drug commonly prescribed to treat panic disorder and certain types of seizures and seizure disorders. It has a long half-life and can stay in your system for 6 to 9 days. It’s important to know how long Klonopin is in your system to avoid any potential interactions.

What Is Klonopin (Clonazepam)?

Klonopin is the brand name for clonazepam, a commonly prescribed anxiolytic drug in the benzodiazepine class. It’s used to treat anxiety disorders, panic disorders, and seizure disorders by increasing the presence of the neurotransmitter gamma-aminobutyric acid (GABA), which produces feelings of calm.[1] It may also be used to treat restless legs syndrome.

The benefits of Klonopin come from its ability to relieve anxiety and stress, but it’s commonly misused or abused for its relaxing effects and euphoria. Misusing Klonopin can significantly increase the risk of physical dependence and addiction, as well as serious withdrawal symptoms.

What Are Klonopin Effects?

The intended effects of Klonopin are to treat seizures or panic attacks. There are some side effects with Klonopin, including:[2]

• Feelings of tiredness
• Depression
• Dizziness
• Irritability
• Coordination problems
• Concentration problems
• Memory and attention problems
• Nausea
• Loss of appetite

Some serious side effects can occur with Klonopin, including:[3]

• Low blood pressure
• Increased heart rate
• Respiratory depression
• Drowsiness
• Difficulty breathing
• Impaired speaking
• Loss of consciousness
• Loss of pleasure
• Suicidal thoughts and actions

Klonopin Drug Interactions

Several drugs may interact with Klonopin, including ketoconazole, itraconazole, nefazodone, fluvoxamine, and cimetidine, which may increase the levels of Klonopin in the blood.[4] Using Klonopin with phenytoin, phenobarbital, and carbamazepine may decrease the levels of Klonopin, making it less effective.[5]

Mixing Klonopin with other benzodiazepines and central nervous system depressants, such as opioids and alcohol, may cause side effects like life-threatening levels of sedation and respiratory depression that can lead to coma or death.

It’s possible to overdose from too much Klonopin or mixing Klonopin with other CNS depressants like alcohol or opioids. The signs and symptoms of a Klonopin overdose may include:[6]

• Confusion
• Slurred speech
• Extreme drowsiness
• Poor reflexes and coordination
• Slowed breathing
• Low blood pressure
• Low heart rate
• Cardiac arrest
• Coma

If you suspect someone is experiencing a clonazepam overdose, call 911 and wait with them until help arrives. Flumazenil can partially or completely reverse the effects of a Klonopin overdose, but it’s still necessary to get medical attention. Flumazenil can cause seizures in some people, which an emergency medical team can manage.

How Long is Clonazepam’s Half Life?

Klonopin’s half-life is 30 to 40 hours.[7] Its major metabolite, 7-amino-clonazepam, is excreted mainly in the urine. Thus, it stays in the body for a longer period than other drugs with a shorter half-life.

A half-life is the time it takes for half of a single dose of a drug to leave the body. For Klonopin, it can take one to two days for just 50% of Klonopin to leave your system. It takes about 5 half-lives for a drug to completely leave your body, which means Klonopin can stay for 6 to 9 days after your final dose.

Klonopin can show up on different drug tests for various periods:

• Urine tests: Up to 3 weeks or possibly up to 30 days after last use[8,9]
• Hair tests: Up to 3 months after last use[10]
• Saliva tests: Up to 5 or 6 days after last use[11]

Several factors can affect how long Klonopin is detectable in a drug test, including age, gender, general health, weight, the dose, when the last dose was taken, how often it’s used, and the concentration and pH of urine.

Can I Quit Taking Klonopin?

If you’re concerned about a drug test or drug interactions with Klonopin, it’s crucial that you don’t stop taking the drug suddenly. Physical dependence, which is when your body becomes used to the presence of a drug and needs it to function, can occur in just two weeks of benzodiazepine use – even if you take it exactly as directed.

If you stop taking Klonopin suddenly after being on it for long periods, severe withdrawal symptoms can occur, such as:[12]

• Anxiety
• Insomnia
• Dizziness
• Irritability
• Sweating
• Vomiting
• Nausea
• Blood pressure changes
• Increased heart rate
• Hallucinations
• Tremors
• Seizures

Some of these clonazepam withdrawal symptoms can be life-threatening, so doctors typically use a taper to wean you off a dose safely and reduce the risk of complications.

Klonopin Addiction

Klonopin, and other benzodiazepines, have a potential for misuse, abuse, and addiction. Some people may become addicted to Klonopin from taking more than they should or at more frequent doses, while others may become addicted from abusing Klonopin with other prescription drugs like opioids.

If you are addicted to Klonopin, medical detox is recommended to manage withdrawal symptoms. Because of the serious risks of benzodiazepine withdrawal symptoms, medical detox provides a medical team to monitor your health, reduce the severity of withdrawal symptoms, and prevent complications.

Once medical detox is complete, it’s important to continue with a Klonopin addiction treatment program that addresses the mental, emotional, and social aspects of addiction. There are many options for drug addiction treatment, including inpatient and outpatient settings with individual and group counseling, addiction education, and behavioral therapies that help you address the contributing factors in addiction and learn healthier habits.

Get Help for Klonopin Addiction

Klonopin is a generally safe drug used to treat anxiety disorders and seizure disorders, but there is a risk of physical dependence and abuse. If you’re struggling with Klonopin addiction, it’s important not to quit cold turkey. Stopping Klonopin suddenly can result in intense and potentially dangerous complications from withdrawal symptoms, so it’s important to start with medical detox as part of a comprehensive Klonopin addiction treatment program.