Ketamine Therapy: Who Isn’t a Good Fit?

Before jumping on the ketamine bandwagon, make sure you’re not at risk for serious complications.

By Patrick McConnell Last Updated: February 12, 2024
Last Updated: February 12, 2024

Ketamine therapy has been capturing the limelight and offering a great deal of hope to people struggling with chronic pain and poor mental health.

Word has spread of people finding relief from depression, anxiety, PTSD, OCD, suicidal ideation, and a growing list of other conditions.

Many clinics boast impressive recovery rates from ketamine therapy, and science tells a promising story of ketamine-induced neuroplasticity and other improvements in brain health [1]. 

There is a lot of hype — and while much of it is justified, ketamine certainly isn’t without its fair share of risks. It’s not for everyone. Some people should definitely NOT take ketamine.

In this article, we’ll unpack factors that deem someone unsuitable for ketamine therapy, explore the most common side effects of it, and explore what options are available for those not fit for this kind of treatment.

Who Isn’t Suitable for Ketamine Therapy?

First of all, nobody should attempt ketamine therapy without consulting a qualified health professional first.

Good clinics will complete thorough medical exams and review your entire medical history long before administering the first dose of ketamine. 

This is essential, as certain heart, liver, and kidney conditions could be dangerous if used in combination with ketamine [2].

A comprehensive check with a psychiatrist is also important. Clinicians are cautious and generally will not give ketamine to those with conditions like schizophrenia or psychosis because scientists are still uncertain how these are affected by powerful mind-altering substances like ketamine.

Studies show other related dissociatives like PCP (phencyclidine) worsen conditions of schizoaffective disorders [3], so there’s a good chance ketamine carries similar implications.

Avoid ketamine therapy if you have any of the following:

  • A history or family history of schizophrenia or psychosis
  • Have not first attempted treatment with other (approved) medications or therapies
  • A history of cardiovascular disease, including hypertension
  • A history of bladder, kidney, or liver disease
  • A history of substance abuse disorder
  • Are unable to understand and provide informed consent
  • Are pregnant or nursing
  • Have known allergies to ketamine or other arylcyclohexylamines

Ketamine Side Effects

Ketamine has been used for over fifty years, and its side effects are well known.

However, as treatments change, what was once a side effect, such as hallucinations, has become part of the drugs’ main benefits.

Some known (side) effects of ketamine include [4]:

  • Lapses in memory
  • Panic attacks
  • Nausea/vomiting
  • Sleepiness
  • Increased blood pressure
  • Nightmares and vivid dreams
  • Bladder or kidney pain

Some other side effects you may have heard of are associated with excessive ketamine use, like bladder or gastrointestinal problems, along with persisting delusions or psychotic episodes. Generally, these disappear when ketamine is stopped; however, in some cases of chronic abuse, permanent damage has been known to occur. 

Perhaps the biggest risk of ongoing ketamine therapy is bladder and kidney damage. A metabolic byproduct of ketamine called norketamine passes intact into the urinary tract, where it erodes the protective lining of the bladder. Repetitive use can lead to severe bladder pain and blood in the urine.

Who Is a Good Candidate for Ketamine Therapy?

Generally, ketamine is given to people who have treatment-resistant symptoms. This means patients have tried just about every other option available but have not found relief.

For example, Spravato intranasal spray, the only FDA-approved ketamine treatment, is specifically approved for “treatment-resistant depression.”

Many ketamine therapy clinics will only accept patients who have tried at least two previous medications with no success.

Good candidates for ketamine therapy are those who: 

  • Have no underlying bladder, kidney, or liver disease
  • Have no history or family history of psychosis or schizophrenia
  • Have no history of substance abuse
  • Have tried at least 2 other medications for managing their depression or anxiety
  • Are able to understand and provide informed consent for the use of ketamine
  • Are not pregnant or breastfeeding
  • Have no underlying problems with blood pressure or other cardiovascular disease

Off-Label Uses for Ketamine

Ketamine is only used “off-label” for treating pain and depression, anxiety, PTSD, and anxiety — meaning it has not undergone the required clinical trials and is, therefore, not FDA-approved.

In the US, ketamine is currently only approved as an anesthetic.

With that said, ketamine is used off-label by doctors for many conditions. As a Schedule III drug in the United States (and equivalently in most countries around the world), this is completely legal — albeit with plenty of risks. Without FDA approval and the numerous phase I, II, and III clinical trials required to earn this approval, there are a lot of unknowns surrounding ketamine.

Some applications, such as in the treatment of traumatic head injuries, have seen controversy in recent years. Some patients have experienced increased intracranial pressure (ICP) after receiving ketamine treatments for this condition [5] — a life-threatening reaction.

Here are just a few of the conditions doctors are using ketamine to support or treat:

  • Anxiety
  • Autism
  • Bipolar disorder
  • Chronic pain conditions
  • Complex regional pain syndrome
  • Depression
  • Fibromyalgia
  • Gender dysmorphia
  • Obsessive-compulsive disorder (OCD)
  • Postpartum depression
  • Post-traumatic stress disorder (PTSD)
  • Season affective disorder (SAD)
  • Substance use disorder
  • Suicidal ideation
Spravato Nasal Ketamine Spray by Johnson & Johnson

What to Consider Before Ketamine Therapy

Before you decide to visit a ketamine clinic or online ketamine provider, here are a few things you should consider.

1. Ketamine Therapy Is Expensive

Ketamine therapy is expensive. Treatments at IV clinics cost thousands of dollars and generally aren’t covered by insurance.

Other methods, like oral ketamine tablets or sublingual lozenges, are cheaper options but don’t provide the same level of efficacy as infusions and generally need to be used long-term to remain effective.

The Spravato ketamine nasal spray is a cheap option for many, not because the medication itself is cheap, but because it’s one of the only ketamine treatments covered by insurance.

2. Getting Access to Ketamine

Ketamine clinics are popping up all over the world. At this point, there are several clinics serving ketamine in every major city in the US, and online ketamine clinics offer at-home ketamine via mail-order lozenges

However, online clinics are rampant with problems, and there are plenty of reasons why these platforms should be avoided until more research becomes available on the implications of long-term treatments.

If you live in an area where ketamine clinics are uncommon, or the ones that are available are booked for months on end, you may need to organize some travel for your treatment — adding additional costs and logistics. 

3. Ketamine Is Not A Quick Solution

Ketamine has demonstrated some pretty impressive results in research over the past 20 years — but it’s far from the quick solution it’s advertised as. 

Ketamine’s antidepressant and anti-anxiety effects last for just 10 days or so before requiring a booster, meaning you need to keep going back for more.

Ketamine itself will not solve your problems, but it can help kickstart the healing process in a big way. Long-term success relies on professional psychotherapy and major lifestyle changes in conjunction with ketamine.

4. The Ketamine Experience Can Be Terrifying

Ketamine is an anesthetic dissociative — producing one of the trippiest, most mind-blowing experiences of any drug available. 

This experience is considered essential for any alleged long-term benefits of the drug. It allows users to take an unbiased look at themselves to spot unconscious habits and impulses that are driving their lives. 

This experience is powerful when combined with skilled psychotherapy, but it’s also terrifying to confront these feelings.

5. Set & Setting Are Critical

As with any psychoactive drug, the set (mindset) and setting (environment and people you’re surrounded by during the experience) are critically important to successful outcomes.

Many clinics simply administer ketamine without putting any emphasis on these other important factors (no adjunctive therapies or pre-sessions, terrible “clinical” environment, rude nurses or doctors, etc.). 

It’s important to vet your practitioner or clinic before undergoing therapy to avoid wasting money and potentially having a terrible experience.

Look for clinics that create a calm, comfortable room and have staff that are kind and empathetic throughout the process.

Ketamine Molecule

FAQs: Ketamine Therapy

Here are some of the most common questions we get asked on the daily about ketamine therapy: 

1. Is Ketamine Addictive?

Yes, ketamine can be addictive if used irresponsibly. While it can be used to treat substance use disorders, it can also be habit-forming.

The goal is to use ketamine to help identify the underlying and unconscious causes of one’s depression, anxiety, or other mental health conditions and then stop taking the ketamine as soon as possible.

Avoid using ketamine as a form of escapism — this never leads to positive outcomes. 

2. Is Ketamine Safe?

Generally speaking, yes, ketamine is very safe. It’s very difficult to overdose on ketamine. This mainly applies to sporadic use. Once every few weeks for a few months is unlikely to cause lasting side effects. 

Ketamine only becomes dangerous when combined with certain medications, certain underlying health conditions, or with long-term, compulsive use.

Long-term ketamine can cause serious bladder disease and has unknown consequences on mental health. 

3. How Much Does Ketamine Cost?

Ketamine therapy is pretty expensive — a single treatment can cost several hundred to over a thousand dollars, depending on the doctor administering the medication.

Online ketamine clinics are cheaper, but the average cost per session still hovers around 200 USD. These treatments generally consist of low-dose ketamine, which hardly compares to the experience of in-person intravenous injections. The efficacy of low-dose ketamine is controversial and, frankly, overhyped at this point.

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  1. Rawat, R., Tunc-Ozcan, E., McGuire, T. L., Peng, C. Y., & Kessler, J. A. (2022). Ketamine activates adult-born immature granule neurons to rapidly alleviate depression-like behaviors in mice. Nature communications, 13(1), 2650.
  2. Zhu, W., Ding, Z., Zhang, Y., Shi, J., Hashimoto, K., & Lu, L. (2016). Risks associated with misuse of ketamine as a rapid-acting antidepressant. Neuroscience bulletin, 32, 557-564.
  3. Mouri, A., Noda, Y., Enomoto, T., & Nabeshima, T. (2007). Phencyclidine animal models of schizophrenia: approaches from abnormality of glutamatergic neurotransmission and neurodevelopment. Neurochemistry international, 51(2-4), 173-184.
  4. Niesters, M., Martini, C., & Dahan, A. (2014). Ketamine for chronic pain: risks and benefits. British journal of clinical pharmacology, 77(2), 357-367.
  5. Kumar, A., & Kohli, A. (2021). Comeback of ketamine: Resurfacing facts and dispelling myths. Korean Journal of Anesthesiology, 74(2), 103-114.