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How long does Ketamine stay in your system after treatment?

Have you heard about ketamine for the treatment of depression and other mental health conditions?

What is Ketamine?


Ketamine is a short-acting anesthetic and analgesic.

Although there is some skepticism about ketamine treatment due to its misuse as the hallucinogenic street drug “Special K,” studies have shown that it has promise as an option for treatment-resistant depression.

This medication has been a huge breakthrough for those struggling with mental health, specifically people with PTSD, anxiety, and depression.

How Does Ketamine Affect the Body?


Ketamine treatments can be administered in many forms, including IV, IM injections, nasal sprays, and oral tablets. However, IV delivery in a controlled setting, administered by a professional, is the safest option, as it lowers the potential for misuse.

Smaller dosages are used for pain relief or sedation, and they leave the body more quickly. Larger dosages can cause dissociation and hallucinations, and can take longer to be removed from the body.

Again, this is why professional administration is necessary. When looking at treatment for depression, a very small quantity goes a long way.



The onset of action is dependent upon the way ketamine is administered. When given as an IV infusion, ketamine takes effect within a matter of seconds. The effects aren’t as immediate if given IM, but they still only take about four minutes.

Still, it can take one to three infusions of IV therapy before a person feels ketamine’s positive effects. Regardless, this medication has a much more rapid onset than other antidepressant medications, which can take up to several weeks to be effective.



The amount of time ketamine remains in your body after administration depends on many factors, including:

  • Body mass
  • Age
  • Rate of metabolism
  • Amount of ketamine administered
  • Method of administration

Your liver removes ketamine from your body by breaking the medication into metabolites. 90 percent of those metabolites are excreted in urine. This process occurs 5 to 30 minutes after administration, and ketamine will exit your body within 10 to 12.5 hours. However, this does not mean that the medication is undetectable on a drug screen.



There are many ways to detect ketamine in your system through a drug test. Never use ketamine for recreational purposes, as this medication can have serious side effects when misused.

Even when safely used as an off-label treatment for depression in a controlled setting, it’s important to know how long ketamine is detectable in your system.

Drug screens can identify ketamine long after your last dose, depending upon the amount of ketamine taken and the drug test performed.

Drug tests can be administered through urine, saliva, blood, or hair samples:

  • Urine test: Ketamine can be detected in a urine sample for up to two weeks after taking the last dose.
  • Saliva test: A saliva test is less reliable, as the test can detect ketamine for only a short time after use.
  • Blood test: Ketamine can be seen in the blood for up to four days.
  • Hair test: Hair follicles can show traces of ketamine for about 90 days following its use.

What Is the Process of Ketamine Infusion?


As mentioned above, it might take one to three treatments to know if ketamine will work for you. However, 70% of individuals see results after the first infusion.

One study involving 25 subjects administered ketamine in six doses for two weeks. After one month, subjects experienced major improvements in symptoms of anxiety and depression.



The need for maintenance infusions depends upon each individual. One person might find that the initial infusions are effective and require minimal maintenance and follow-up. Someone else might find that additional medication is necessary for months or even years to maintain mental wellbeing.

If extending treatment for longer periods, it’s important to be attentive and aware of possible side effects.

Where Can I Find Ketamine Treatment?


If you are interested in trying Ketamine treatments for a mental health condition, Pasithea Therapeutics is a great place to start.

Pasithea Therapeutics is a biotech company that has researched ketamine’s promising effects on mental health and brain disorders. Pasithea Therapeutics offers IV-administered ketamine by a CRNA or anesthesiologist, given in your home or office.

Whatever your needs, Pasithea Therapeutics can help you find a ketamine treatment that works for you.

The Takeaway


Ketamine is a medication used off-label for treatment-resistant depression, which has been a great move forward in mental health. It may take one to three treatments before seeing results; however, many people respond to treatment on the first infusion.

The time ketamine stays in the body depends upon several factors, including the quantity of the medication given, age, body mass, metabolic rate, and route of administration.

Typically the medication exits the body in 10 to 12.5 hours, but ketamine can be detected on a drug screen beyond this time depending upon the specific drug test.



Repurposing Ketamine in Depression and Related Disorders: Can This Enigmatic Drug Achieve Success? | Frontiers

How Long Does Ketamine Stay in Your System? | Addiction Group

How Long Does Ketamine Stay in Your System? | American Addiction Centers

Efficacy and safety of ketamine in the management of anxiety and anxiety spectrum disorders: a review of the literature | Duke

Efficacy of ketamine therapy in the treatment of depression | NCBI

Ketamine for Depression, 4: In What Dose, at What Rate, by What Route, for How Long, and at What Frequency? | NCBI

Ketamine for Depression: What is Ketamine Treatment? | PsyCom