Updated on April 3, 2024
5 min read

How Long Does Ketamine Stay in Your System?

Key Takeaways

Ketamine (Special K, K, Vitamin K) is a dissociative drug. People often abuse it for its hallucinogenic and anesthetic properties. Sometimes, they’ll mix it with other drugs like marijuana and ecstasy.

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How Long Does Ketamine Stay in Your System?

Ketamine’s effects come on fast and don’t last long, but the drug can still be detected in your system long after you’ve taken it. The time frames for detecting ketamine use will increase with high doses.

Urine Test

The detection window for testing a urine sample is quite long. It can be seen in the urine for about two weeks.

Urine samples are the most common drug test for ketamine. It is inexpensive, non-invasive, and has a large detection window.

Saliva Test

Saliva tests are not often used to test for ketamine because it has a small detection window. It can still detect ketamine in your saliva for 24 hours.

Blood Test

Ketamine can be detected in the blood for about four days. However, it’s most effective within the first 24 hours. 

Because of the high cost, invasiveness, and short detection window, blood tests aren’t commonly used to detect ketamine.

Hair Test

Ketamine can be detected in hair follicles for about 90 days. For long-term ketamine users, the drug can be detected in the hair for up to 12 months.

Nail Test

Nail tests won’t give doctors a history of ketamine use. However, it’s still effective at detecting the drug. Ketamine can be detected in your nails for up to 12 months.


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What is The Half-Life of Ketamine? 

The half-life of ketamine is approximately 45 minutes. The effects may last much longer depending on how much ketamine is consumed.

It can take 4-5 half-lives to eliminate the drug from your system. This means that healthy adults need 10 to 12 hours for their bodies to eliminate the drug. 

However, the drug can still be detected in your system after it has been eliminated from your body. Some tests detect it months after a person’s last use.

What Factors Affect How Long Ketamine Stays in Your System?

Various factors affect how long Ketamine stays in your system. These factors determine how well your body eliminates ketamine.

These factors include:

  • Age and overall health: Younger and healthier people can clear ketamine from their system much faster than older people
  • Hydration: Ketamine will leave your body faster if you’re well-hydrated due to urination
  • Metabolism: People with faster metabolisms can quickly break down and eliminate the drug
  • Kidney and liver function: A healthy liver and kidney can process the ketamine out of your system without interruption
  • Body mass: A higher body mass means you can metabolize ketamine faster than people with smaller bodies
  • Ketamine Dosage: A higher dosage of ketamine will require more time to get rid of
  • Frequency of use: Frequent ketamine use can cause a build-up in your body, making the drug stay in your system longer
  • Polysubstance use: Taking ketamine alongside other drugs will cause your body to process both substances simultaneously, making the process take longer

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How Long Do The Effects of Ketamine Last?

The duration of ketamine’s effects depends on how much you’ve taken and how high the dosage is. Typically, the effects of Ketamine last anywhere between 30 minutes to 1 hour.

The time it takes to feel the effects of ketamine can vary depending on how you take it. The effects are usually felt around 10-15 minutes later when snorted. 

When taken as a tablet, the effects can take about 20 minutes. However, if ketamine is directly injected into the bloodstream, you’ll immediately feel the effects.

Ketamine can make you feel the following:

  • Impaired feelings of pain
  • Altered perception of time
  • Dream-like hallucinations
  • Feelings of euphoria

Common Signs of A Ketamine Overdose

Overdosing on ketamine can be dangerous. It can slow the heart rate and cause a significant impact on your body, leading to: 

  • Loss of consciousness
  • Coma
  • Permanent psychosis
  • Tissue damage
  • Death

Accidentally overdosing on ketamine is common. Here are some signs to look out for in a ketamine overdose:

  • Vomiting
  • Drowsiness
  • Difficulty speaking or impaired speech
  • Impaired vision
  • Muscle twitching
  • Shortness of breath
  • Confusion
  • Altered perception of reality
  • Dissociation
  • Convulsions
  • Seizures
  • Unconsciousness
  • Hearing disturbances

If you, a loved one, or someone you know has overdosed on ketamine, contact emergency medical help immediately.

Ketamine Withdrawal Symptoms

Ketamine withdrawal can be unpleasant and life-threatening if not handled properly. Ketamine withdrawal symptoms include:

  • Stomach cramps
  • Bladder pain
  • Visual and auditory problems
  • Increase heart rate
  • Sweating
  • Severe depression
  • Anxiety
  • Aggression and irritability
  • Paranoia
  • Psychosis
  • Panic attacks
  • Insomnia
  • Suicidal thoughts
  • Ketamine cravings

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Treatment for Ketamine Misuse & Addiction

Ketamine abuse can severely harm users’ physical and mental health. Treatment options are available if you or a loved one is struggling with misuse and/or addiction. 

A medically-monitored detox will remove the toxins from your body and help users avoid relapsing when they experience intense cravings. The detoxification process is safest under the supervision of a healthcare professional who can help the user to manage withdrawal symptoms during the detox period.

Click to learn more about the most effective types of addiction treatment:


Depending on the type of test, ketamine can be detectable in your system for days or weeks. It can even be detectable for months after your last use.

Several factors affect how long ketamine stays in your system. You can feel ketamine’s effects for 30 minutes, lasting up to an hour.

Ketamine can be dangerous, and its side effects can be permanent and even fatal. Seek immediate medical attention if you notice someone overdosing on ketamine or experiencing withdrawal symptoms.

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Updated on April 3, 2024
10 sources cited
Updated on April 3, 2024
  1. 10 Signs Someone Is High on Ketamine.” Sunrise House, 2022.
  2. How Long Does Ketamine Stay in Your System? (Blood, Urine & More): Delphi.” Delphi Behavioral Health Group, 2019.
  3. Ketamine.” DEA.
  4. Ketamine.” National Center for Biotechnology Information. PubChem Compound Database, U.S. National Library of Medicine, 2022. 
  5. Ketamine: Is It Addictive? (Signs, Symptoms & Treatment): Delphi.” Delphi Behavioral Health Group, 2019.
  6. Kurdi et al. “Ketamine: Current Applications in Anesthesia, Pain, and Critical Care.” Anesthesia, Essays and Researches, Medknow Publications & Media Pvt Ltd, 2014.
  7. Mountainside. “Ketamine.” Mountainside Addiction Treatment Center.
  8. Orhurhu, V. “Ketamine Toxicity.” StatPearls, U.S. National Library of Medicine, 2020. 
  9. Rosenbaum, S. “Ketamine.” StatPearls, U.S. National Library of Medicine, 2020.
  10. Williams et al. “Attenuation of Antidepressant Effects of Ketamine by Opioid Receptor Antagonism.” American Journal of Psychiatry, 2018.

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