Ketamine for Suicidal Ideation: Rapid Effects and FDA Status

Ketamine can reduce suicidal thoughts quickly in some people. Randomized trials have measured improvement within hours or by the next day, across more than one study.

But rapid improvement in suicidal thoughts is not the same as preventing suicide attempts or suicide deaths. No randomized trial has shown the second thing.

The strongest direct evidence involves IV racemic ketamine. Spravato carries a related FDA indication that is widely misread. In the major acute-crisis trials, ketamine was given alongside broader psychiatric care rather than as a substitute for it.

Suicidal Thoughts and Suicide Prevention Are Different Outcomes

Almost all ketamine research here measures one thing: how strongly or how often someone reports suicidal thoughts after treatment. That matters clinically.

A suicide attempt is a different outcome. A suicide death is a third.

Trials tracking the Scale for Suicidal Ideation, the Beck Scale for Suicide Ideation, the Columbia scale, or a single suicide item on a depression questionnaire can show that thoughts changed. They can't show that attempts or deaths became less common.

The reason is statistical. Attempts and deaths are far rarer events, so detecting a difference requires studies many times larger than any ketamine trial run so far. A 2026 review in the American Journal of Psychiatry makes the point directly: these trials aren't powered for suicidal behavior.

How Quickly Can Ketamine Reduce Suicidal Thoughts?

Fast, in the trials where it worked. Effects have been recorded within the first few hours, at 24 hours in several controlled trials, and by day 3 in the largest study. That's much quicker than antidepressants, which usually take weeks.

One caution. A group difference at 24 hours doesn't mean every person improves in 24 hours. Averages hide people who responded slowly or not at all.

The Strongest MDD Trial Found Improvement Within 24 Hours

Grunebaum and colleagues randomized 80 adults with major depressive disorder and clinically significant suicidal ideation, defined as scoring at least 4 on the Scale for Suicidal Ideation. About 54 percent were already taking an antidepressant.

Participants received IV ketamine at 0.5 mg/kg or IV midazolam at 0.02 mg/kg. Midazolam is an active control, harder to see through than saline.

At 24 hours, the ketamine group's suicidal ideation score fell 4.96 points further than the midazolam group's. Using a threshold of at least 50 percent improvement, 55 percent of the ketamine group responded compared with 30 percent on midazolam.

Two cautions. This was one trial of 80 people under controlled research conditions, so 55 percent isn't a rate to expect for yourself. And response meant scores dropped by half, not that suicidal thoughts disappeared.

Did the Suicidal Thoughts Improve Only Because Depression Improved?

Partly, but not entirely.

The same trial tested this. Improvement in depression accounted for about 33.6 percent of ketamine's effect on suicidal ideation, and the authors concluded the effect was partially independent of the antidepressant response.

That finding is easy to overstate. A mediation analysis can suggest depression improvement doesn't explain everything. It can't demonstrate a separate biological pathway, and nobody has shown one.

The Largest Acute Suicidal-Ideation Trial

Abbar and colleagues published the biggest trial of its kind in 2022, across seven French teaching hospitals. It enrolled 156 adults voluntarily admitted with current suicidal ideation, mostly severe.

The population was mixed by design: bipolar disorder, depressive disorders, and other psychiatric diagnoses. Everyone received usual care. On top of that, 73 people were randomized to two 40-minute IV ketamine infusions at 0.5 mg/kg, given at baseline and 24 hours later, and 83 to saline.

The primary outcome was full remission of suicidal ideation at day 3. Ketamine reached it in 46 of 73 people, or 63.0 percent. Placebo reached it in 25 of the 79 participants with day-3 data, or 31.6 percent. The odds ratio was 3.7.

Diagnosis Changed the Result in the Abbar Trial

The trial stratified by diagnosis, and the day-3 results split sharply. Among participants with bipolar disorder, 84.6 percent on ketamine reached remission versus 28.0 percent on placebo. Among those with a depressive disorder, it was 42.3 percent versus 35.7 percent, which was not statistically significant. In the other-diagnoses group, 61.9 percent versus 30.8 percent, also not significant.

The interaction between treatment and diagnosis was statistically significant.

Read that carefully. It doesn't establish that ketamine works better for bipolar depression. It's a subgroup result from a single trial, the bipolar group held 51 people, and the confidence intervals were wide. What it does suggest is that results from one diagnostic group shouldn't be assumed to apply to another. Our guides on ketamine for bipolar depression and ketamine for depression cover those separately.

A Small Bipolar Trial Was Less Conclusive

An earlier pilot points the other way. The same research group randomized 16 people with bipolar depression and clinically significant suicidal thoughts to ketamine or midazolam.

Suicidal ideation fell about 5.84 points further after ketamine at day 1. The result did not reach statistical significance, with a p value of 0.074 and a confidence interval crossing zero.

The authors called it a feasibility study needing replication. It's a counterweight to the dramatic bipolar subgroup number above.

Newer Evidence Includes an Oral Ketamine Trial

A 2025 trial randomized 80 adults with major depressive disorder and expressed suicidal ideation to a single dose of oral racemic ketamine at 3 mg/kg or oral midazolam. Suicidal ideation was rated with the Modified Scale for Suicidal Ideation at 4 hours, day 3, and day 7.

Scores were lower with ketamine at all three points. Depression scores were lower at 4 hours and day 3.

That's a real result from a controlled trial, and one study. It doesn't establish oral ketamine as a treatment for acute suicidal ideation, and it says nothing about at-home or telehealth ketamine programs, which weren't studied.

What Do the New 2026 Meta-Analyses Add?

Two arrived this year, and both need reading past the abstract.

The first, in JAMA Psychiatry, pooled 26 randomized trials with 1,166 people having a major depressive episode. Suicidal symptoms were lower with ketamine at 24 hours and at one month. But the entry requirement was a depressive episode, not clinically significant suicidal ideation, so many included trials were depression studies that measured suicidal thoughts secondarily.

The second, in Brain and Behavior, pooled 10 trials with 649 participants comparing ketamine against midazolam. It found short-term advantages on two suicidal-ideation measures, rated moderate certainty after downgrading for inconsistency. Its authors call ketamine much more effective. That phrasing runs ahead of the data, since heterogeneity sat around 63 percent and the pooled effects shrank noticeably in sensitivity analysis.

An earlier review sorted this more usefully. It counted 12 randomized trials with reduction of suicidal ideation as the primary objective and 14 where it was secondary. Those aren't equivalent evidence.

How Long Does the Improvement Last?

The distinction that matters is what stayed randomized.

In the Grunebaum trial, improvement was described as maintained up to six weeks. That follow-up was uncontrolled, with optimized standard pharmacotherapy and open ketamine offered to some midazolam nonresponders. It can't be credited to the original infusion.

In the Abbar trial, remission at six weeks was 69.5 percent on ketamine and 56.3 percent on placebo, and the difference was not statistically significant.

The 2025 oral trial held a significant difference through day 7. The 2026 JAMA Psychiatry pooled analysis still found a signal at about one month, though many of its trials didn't recruit people specifically for suicidal ideation.

So the acute effect is much better established than durable benefit. A pooled signal around one month does exist. Longer-term controlled evidence stays thin, and individual trial advantages tend to narrow over time.

Does Ketamine Prevent Suicide Attempts?

We don't know. This is the clearest gap in the field.

A 2023 systematic review found no studies at all on the prevention of suicidal acts or mortality. The 2024 VA and Department of Defense guideline concluded there's insufficient evidence to recommend for or against ketamine or esketamine for reducing suicide or suicide attempts. Its work group had very low confidence in that evidence.

That same guideline made a separate, weaker recommendation. It suggests offering ketamine infusion as an adjunctive treatment for short-term reduction in suicidal ideation in people with major depressive disorder. Two recommendations, two different outcomes.

What Happened to Suicide Attempts in the Largest Trial?

Abbar reported the numbers. Over six weeks, 6 of 73 people in the ketamine group attempted suicide, about 8.2 percent, compared with 8 of 83 in the placebo group, about 9.8 percent. One person in the ketamine group died by suicide during follow-up, and the study's oversight committee judged the death unrelated to the treatment.

Don't read those two percentages as a result. The trial wasn't designed or sized to compare attempt rates, and a gap that small in a study this size means nothing in either direction.

The investigators concluded that resolving a suicidal crisis takes more than medication.

Spravato's FDA Approval Is Easy to Misunderstand

Here is the exact indication. Spravato is approved for depressive symptoms in adults with major depressive disorder with acute suicidal ideation or behavior, in conjunction with an oral antidepressant.

Read what that says. The approved target is depressive symptoms. The suicidal ideation describes who the patient is, not what the drug is approved to fix.

The label's Limitations of Use section makes it explicit. Effectiveness in preventing suicide has not been demonstrated. Effectiveness in reducing suicidal ideation or behavior has not been demonstrated. Use does not remove the need for hospitalization when that's clinically warranted.

Those sentences appear on the label itself.

What Did the Spravato ASPIRE Trials Actually Show?

Two phase 3 trials, ASPIRE I and ASPIRE II, enrolled 226 and 230 adults. All had major depressive disorder with active suicidal ideation with intent and needed psychiatric hospitalization. Everyone received comprehensive standard care, including hospitalization and newly started or optimized antidepressants. On top of that they received esketamine nasal spray or placebo nasal spray.

The primary endpoint in both was change in depression on the MADRS at 24 hours. Both met it, with a difference of about 3.8 points in ASPIRE I and 3.9 in ASPIRE II.

The key secondary endpoint was a clinician-rated severity measure for suicidal thinking. In neither trial was the between-group difference statistically significant.

That is why the label reads the way it does.

Ketamine and Spravato Have Different Evidence

They're related drugs with different records, and merging them produces false claims.

IV racemic ketamine is where the direct suicidal-ideation signal lives. The 2023 review put it plainly: IV racemic ketamine beat control drugs within the first 72 hours, while intranasal esketamine did not differ from placebo in the large trials.

Spravato's registration program showed faster improvement in depressive symptoms among acutely suicidal patients. That's a real result. It isn't the same result.

Why Did Suicidal Thoughts Improve in the Spravato Placebo Groups Too?

Because those groups weren't untreated.

Everyone in ASPIRE was hospitalized, seen frequently, and started on or switched to an optimized antidepressant. Suicidal thinking improved substantially in both arms.

That doesn't make hospitalization a placebo. It means the comparison was esketamine plus intensive care against intensive care alone, and the question was what the nasal spray added on top. For depressive symptoms, a measurable amount. For the clinician-rated suicidal thinking measure, no significant difference.

Does Ketamine Work the Same Across Diagnoses?

No evidence establishes that. Most trials enrolled people with unipolar major depression. Abbar's mixed population hints that diagnosis matters, and its subgroups pointed in different directions.

Bipolar depression, PTSD, borderline personality disorder, and mixed presentations each have their own literature, mostly thin. Findings from depression trials shouldn't be stretched to cover everyone experiencing suicidal thoughts.

What About Borderline Personality Disorder?

One controlled trial has tested this directly. A 2023 pilot randomized 22 adults with borderline personality disorder and current suicidal ideation to a single IV infusion of ketamine at 0.5 mg/kg or midazolam at 0.04 mg/kg. Participants were followed for four weeks.

Suicidal ideation was the primary outcome, measured with the Beck Scale for Suicide Ideation. Scores fell in both groups, and the difference between them was not statistically significant. Borderline symptom scores didn't separate either, and the depression difference was a numerical trend.

The trial did find better socio-occupational functioning in the ketamine group at day 14. Ketamine also produced more intense dissociation during the infusion, which resolved within 40 minutes.

Two participants in the ketamine group later experienced acute distress and suicidal ideation during the fourth week and required urgent psychiatric evaluation. One was discharged after an overnight emergency department visit. The other received further ketamine infusions as part of inpatient care. With 22 participants, the study can't establish whether those events were related to ketamine.

With so few people and relatively low baseline suicidal ideation, the study had little power to detect a difference. The single infusion was acutely tolerated here. But the trial didn't establish an effect on suicidal ideation, and its size prevents firm conclusions about safety.

What About Repeated Ketamine?

Common in practice, thin in evidence for this outcome.

The 2026 JAMA Psychiatry analysis found repeated infusions reduced suicidal symptoms by the end of treatment, similar in size to what single infusions achieved at 24 hours. That tells you repeated dosing does something. It doesn't tell you it prevents suicidal thinking from returning, or how long anyone should continue.

The 2026 review notes maintenance strategies remain uncertain. No standard schedule exists for this outcome, and study protocols aren't treatment recommendations.

Ketamine Is Not a Replacement for Emergency Psychiatric Care

The major acute-crisis trials ran inside real psychiatric care. Abbar's participants were hospitalized, ASPIRE required hospitalization, and Grunebaum's participants were closely monitored with ongoing medication management.

The Spravato label says directly that treatment does not remove the need for hospitalization when clinically warranted.

An outpatient ketamine clinic isn't an emergency service, and a clinic directory isn't either. When someone is in immediate danger, emergency evaluation comes first.

Is Ketamine FDA Approved for Suicidal Thoughts?

Generic racemic ketamine: no. It's approved as an anesthetic, and psychiatric use is off-label.

Spravato needs a full sentence. It's FDA approved to treat depressive symptoms in adults with major depressive disorder who have acute suicidal ideation or behavior, alongside an oral antidepressant. Its effectiveness in preventing suicide, or in reducing suicidal ideation or behavior, has not been demonstrated.

What Should You Ask a Ketamine Provider?

Are you treating my depression, my suicidal thoughts, or both?
What evidence supports the treatment you're recommending?
Are you using racemic ketamine or Spravato?
Is this treatment FDA approved for the outcome you're describing?
How will suicidal thoughts be measured, and how often?
What happens if they return within days?
How does this fit with the rest of my psychiatric care?
What's your process if my risk increases?
Do you coordinate with my psychiatrist or therapist?
When would you recommend emergency or inpatient care instead?

Finding a Provider

KetamineFinder can help you find providers for an ongoing treatment conversation. It can't triage a crisis.

Not every clinic treats acute suicidal ideation, higher-risk patients, bipolar disorder, or complex psychiatric presentations. A clinic set up for routine depression infusions may not be the right setting for someone in an acute crisis, and a careful one will say so.

Our guide on choosing a ketamine clinic covers what to check, and Spravato treatment explains how certified clinics work. You can search clinics near you.