What Is Ketamine Infusion Therapy?

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What Is Ketamine Infusion Therapy?

Ketamine infusion therapy is a promising ketamine treatment that helps mental health conditions including treatment-resistant depression and anxiety disorders.

Ketamine, originally developed as anesthesia, was first discovered to work similarly to antidepressants as early as 1975. Early reports from street ketamine users showed promise in its antidepressant effects, but they were dismissed because it was an illegal substance.

Researchers began studying it in humans in the late 1990s, with a first study published in 2000 that showed promising results for ketamine infusion therapy.

In 2019, Spravato (esketamine) was approved by the FDA for treatment-resistant depression (depression that hasn’t responded to at least two medicines). However, this is more common than you would think—more than 50% of people don’t respond to the first antidepressant they try.


Ketamine infusions have been shown to be the kind of ketamine treatment that your body absorbs the best,but they are not the only kinds of ketamine treatment out there. Which one you go with may depend on your preferred setting (clinic vs. home) and, of course, the price.

  • Ketamine infusions: These are delivered intravenously in a hospital or clinic setting and typically last around 40 minutes.
  • Intramuscular: A single shot of ketamine is injected into one of your larger muscles (thigh or arm), and similarly to intravenous, the experience lasts around 40 minutes, and is administered in a hospital or an office setting.
  • Lozenge (also known as troche): Lozenges are taken orally, and they may be taken either at home or in a clinic setting. They may be prescribed either as the primary treatment or as a maintenance measure in between intramuscular, intravenous, or intranasal treatments.
  • Nasal: There are two different types of nasal ketamine. Spravato is administered in a doctor’s office, and you must be monitored for side effects for two hours after taking it. However, Spravato is the only type of ketamine treatment that is FDA-approved for depression, so you may be able to get your insurance to cover some of the cost. (All other uses of ketamine are off-label.) The other option is getting a ketamine nose spray at a compounded pharmacy, where they specifically mix the spray to your own needs, as determined by your doctor.

What Ketamine Infusion Therapy Can Help With

Ketamine infusion therapy helps with a number of psychiatric conditions, but it is most commonly used in those with treatment-resistant depression, a form of major depressive disorder. You are likely to be diagnosed with treatment-resistant depression if you have tried more than two antidepressant treatments and have not responded adequately.

Ketamine infusions may also help with acute suicidality or chronic suicidal ideation. 

Other conditions that ketamine may help:

If you are having suicidal thoughts, contact the National Suicide Prevention Lifeline at 988 for support and assistance from a trained counselor. If you or a loved one are in immediate danger, call 911.

For more mental health resources, see our National Helpline Database.

Benefits of Ketamine Infusion Therapy

If you have tried several antidepressants before, then you know that it takes anywhere from four to six weeks to start seeing the full effect of the medicine—if you see any effects at all. Someone who is suicidal does not have the luxury of waiting several weeks for a medicine to kick in.

In one study, 88% of the participants given a ketamine infusion in the emergency room had their suicidal ideation go away in just 90 minutes.

It is thought that ketamine infusions work by inducing the production of glutamate, a neurotransmitter in the brain. Abnormal levels of glutamate have been linked with depression. The glutamate leads the brain to form new connections and repair damaged ones, increasing its adaptability.

The new neural pathways—think of them as new roads in your brain—allow you to create more positive thoughts and, therefore, behaviors. This is compared to traditional antidepressants, which only work as long as they are in your system.

Symptoms that may improve include a depressed mood, suicidality, helplessness, and worthlessness.


Ketamine infusion therapy has been hailed as a transformative treatment because of its high rate of response.

In one study, 85% of patients experienced a remission in their depressive symptoms (defined as at least a 50% reduction in symptoms). However, ketamine infusions aren’t necessarily a cure. Patients relapsed (some symptoms returned) on an average of 19 days after, but some did not relapse for more than three months.

Things to Consider

If you are thinking about receiving ketamine infusion therapy, you'll want to consider some side effects beforehand. Also, if you're dealing with a mental health condition, you might not be eligible to receive this kind of therapy.

Let's also discuss some tips that might be helpful to you if you receive ketamine infusion therapy.

Side Effects

Ketamine infusion therapy is delivered at a dosage that is less than you would get if you were receiving ketamine for anesthesia, but some of the side effects might seem similar. The good news is that they typically go away either by the time the infusion is over or within a few hours.

Below are some potential side effects:

  • Nausea
  • Dizziness
  • Double vision
  • Drowsiness
  • Confusion

Who It Isn’t For

Although ketamine infusions may generally be well-tolerated by many, there are several factors that might prevent you from being able to try ketamine infusions. For example, if you have schizophrenia, high blood pressure that is not otherwise well-managed, or if you are acutely alcohol-intoxicated, you will not be able to receive ketamine infusions.

Tips and Tricks

You have taken the first step by deciding to get ketamine infusion therapy for your mental health. Here are a few things you can do to maximize your experience:

  • Minimize stress. Avoid anything stressful—like reading or watching the news—before your treatment. You want to be in the best frame of mind you can be going into it.
  • Find a good playlist. The right kind of music will help you relax and will set the soundtrack for your experience. Music without words is recommended, as hearing the lyrics may be too distracting.
  • Meditate. If you have a meditation practice, you may want to meditate just before starting the ketamine infusion to slow down your racing thoughts a little.
  • Integrate with therapy. If you are already in therapy, it will be helpful for you to discuss your expectations before and process your experience afterward with your therapist.

How to Get Started With Ketamine Infusion Therapy

If you're looking to start ketamine infusion therapy, this section will discuss how you can find a provider who offers this kind of treatment and what you can expect at your first appointment.

How to Find a Provider for Ketamine Infusion Therapy

If you’ve decided to take this step, you may be overwhelmed with where to begin to look. If you are in a major city, you may have many options, but how do you know which ones are legitimate?

The American Society of Ketamine Physicians, Psychotherapists & Practitioners (ASKP) directory is a good place to start. Its members must agree to a strict set of standards and ethics.  

What Will My First Appointment Be Like?

Your first meeting will likely be an intake session, where the doctor will ask you about your depression, what you’ve already tried and what medicines you are currently taking.  

This appointment is also your opportunity to ask them questions. If they decide you are a good candidate for treatment—and you feel comfortable with them—you will schedule your first infusion.

Typically, the standard protocol involves about six infusions over the course of two to three weeks, and then you will check in with the doctor on how to proceed from there. Some people will go back roughly monthly for “booster” infusions, and some will be considered “in remission.”

Your first ketamine infusion should last about 40 minutes. The provider will make sure that you are comfortable before you get started, and they will likely put a pulse oximeter on your finger and a blood pressure cuff on your arm so that they can monitor your vitals during the infusion. 

They may offer you an eye mask and headphones, or you may want to bring your own. Some people find it more pleasant to have an eye mask on and listen to calming music. You may begin to feel some of the effects of the ketamine within a few minutes. You might feel a “floaty” sensation or you may feel like you are not quite in your body. This is all normal and mildly dissociating is part of the process. Rest assured that these feelings will pass.

Once the infusion is over, you will likely still feel a little out of it as the ketamine wears off. You will be monitored for another 20 to 30 minutes, and then you can leave. Have a ride (whether a loved one or a ride-share) home, because you will not be able to drive.

Rest, if you can, when you get home, and take advantage of your brain’s ability to create new thoughts and habits.

10 Sources
Verywell Mind uses only high-quality sources, including peer-reviewed studies, to support the facts within our articles. Read our editorial process to learn more about how we fact-check and keep our content accurate, reliable, and trustworthy.
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By Theodora Blanchfield, AMFT
Theodora Blanchfield is an Associate Marriage and Family Therapist and mental health writer.