Is Ketamine Safe?

How to interpret different claims about the safety of this treatment for severe depression

Originally published on Psychology Today

In February 2023, there was an extensive article published in the New York Times that raised questions about the safety of ketamine, a treatment for severe depression and suicidality that has been gaining more ground recently. The article interviewed dozens of patients and clinicians and cited concerns especially around addiction, bladder dysfunction, and lack of long-term safety data. The article ultimately called ketamine a “fraught new frontier” in treatment for depression in large part because of these concerns. But what does the existing evidence say about each of these concerns?

First of all, it is important to note that experts interviewed for the Times piece did say that these outcomes were exceedingly rare at the doses and frequencies that most patients receive ketamine. The concern really stems from at-home treatments in which some people end up getting more ketamine than they should. This brings us to the first concern: addiction.

How common is addiction to ketamine among people who receive the drug in the traditional way, e.g. through a licensed provider at a clinic or infusion center? Research shows that ketamine addiction after use in a treatment center for depression is exceedingly rare. It is true that ketamine can be addictive when used recreationally, but as far as these things go, ketamine is generally less addictive than alcohol, nicotine, and opioids. So it has a potential for abuse, but the abuse potential is relatively low in most people seeking treatment for depression and receiving ketamine in a controlled manner. The question is a bit murkier for home use of ketamine for depression, which is gaining in popularity. In these cases, the highest risk probably still lies with people who have experienced other addictions. Caution should be taken in these cases both in the clinic and at home.

Onto the second claim: does ketamine cause bladder dysfunction? Ketamine Bladder Disorder or ketamine-induced cystitis is a painful condition that causes urinary frequency and urgency and pelvic pain or pressure. However, this condition generally occurs only with very high usage of the drug, much higher than what most patients are getting in the clinic. Once again, this is an exceedingly low risk in controlled conditions but can be more of a risk if people receiving the drug at home are abusing it.

As for the long-term effects of using ketamine for depression, it is true we do not have decades of data to confirm long-term safety because the drug has only been used for treatment-resistant depression more recently. However, even this concern needs to be put into perspective. Ketamine for treatment-resistant depression is indicated for people who have not responded to a wide range of antidepressants and other evidence-based treatments for depression or have significant suicidal thinking, impulses, and behaviors. In many cases, people’s lives are absolutely in the balance, and ketamine offers a treatment option that can offer significant relief for some people from a serious, debilitating, and life-threatening illness. For that reason, many people suffering with severe depression that doesn’t respond to other interventions may make the reasoned decision to undergo ketamine treatment.

Any medication comes with risks and benefits of course. In this case, the risk to the lives of many patients suffering from treatment-resistant depression is too great to ignore.