Panic Attack vs Anxiety Attack: The Real Difference
One of these terms is in the DSM-5-TR and one is not. How to tell the difference, why the wording changes what gets treated, and what actually works for panic.
Written by Dr. Gino Ang, MD, Board-Certified Anesthesiologist | Medically reviewed by Dr. Gino Ang, MD | Est. reading time: 10 minutes
There is a conversation I have had enough times to recognise it from the first sentence. Someone finishes their infusion series, felt noticeably better for three or four weeks, and then watched it fade. They come back asking whether they need more infusions.
Sometimes the answer is yes. But often the more useful question is what was happening in those three or four weeks while they felt better, and the honest answer is frequently nothing. They felt well, so they did not start therapy, did not change anything, and waited.
That is the part of this treatment that gets explained least well, including by clinics. So here is how I think about it, and what the research does and does not support.
This naturally raises important questions:
The window idea, stated carefully
Ketamine does not work the way a daily antidepressant works. It acts on the glutamate system rather than serotonin, and the current leading explanation is that it briefly increases the brain’s capacity to form new connections. Researchers call this synaptic plasticity. Clinics tend to call it the neuroplasticity window.
Two things about that phrase deserve more honesty than they usually get.
First, most of the direct evidence for the synaptic changes comes from animal studies. The human picture is built on imaging work, symptom data and inference. It is a well-supported hypothesis, not a settled mechanism.
Second, nobody can tell you precisely how long your window lasts. You will see confident claims of “seven to ten days” on clinic websites. I would not put a number on it. What we can say is that the period after an infusion appears to be a time when change is more available than usual.
Which leads to the practical point, and it is almost embarrassingly simple.
The window is an opportunity, not a treatment. Ketamine appears to make the brain more able to change. It does not decide what it changes into. If nothing is actively working on the patterns underneath, the most likely outcome is that things settle back roughly where they were.
What the research actually shows
This is where I have to be careful, because the evidence here is genuinely mixed and most pages on this topic quote only the encouraging half.
Depression: encouraging, then complicated
A team at Yale ran an open-label study in which patients received four ketamine infusions over two weeks and began cognitive behavioural therapy 24 to 48 hours after the first infusion, continuing for twelve sessions in total. Among the people who responded, the median time to relapse was around 12 weeks. The authors noted that comparable figures in earlier relapse-prevention work had been in the range of 17 to 24 days.
That is a striking difference. It was also 16 participants, open-label, with no control group, which is a study design that tends to flatter whatever is being tested.
The same group then ran the properly controlled version. Forty-two patients consented, 28 responded to a six-infusion series and were randomised either to CBT or to treatment as usual for 14 weeks, with no further ketamine. The result: the primary outcome was not met. On the clinician-rated depression scale the effect size was moderate at d = 0.65, but the statistical interaction did not reach significance. On the patient-reported measure, the CBT group did show significantly better sustained improvement.
So what do you do with that?
My reading, and it is a reading rather than a fact: the signal is real but the trial was small enough that it could not prove it. A moderate effect size with a non-significant result in 28 people is the classic shape of a study that was underpowered rather than a treatment that does nothing. But I am not going to tell you the depression evidence is conclusive, because it is not, and any clinic that says otherwise has not read the second paper.
OCD: the clearest signal of the three
Ironically, the condition where ketamine alone performs worst is where the combination looks best.
A 2026 systematic review found that single infusions produced a rapid anti-obsessional response in roughly half to 60 percent of participants, but that the effect generally faded within about a week when ketamine was used on its own. When infusions were combined with exposure and response prevention therapy, improvements were reported as sustained for weeks to months.
That contrast is about as close to a demonstration of the window argument as the literature currently offers. If you are considering ketamine for OCD, our piece on mental compulsions and ERP therapy covers why the therapy component is not optional there.
PTSD: promising, early
The controlled evidence for ketamine in PTSD is reasonably strong on its own, with a trial showing 67 percent of participants achieving meaningful symptom reduction against 20 percent on an active comparator, and median benefit lasting roughly four weeks.
Work pairing infusions with trauma-focused therapy, including written exposure therapy, is at the open-label stage. The direction is encouraging and it fits the mechanism. It is not yet proof. We go into the broader picture in our article on complex PTSD and why treatment sequencing matters.
Esketamine with CBT
A randomised trial called CBT-ENDURE tested esketamine plus 16 weeks of CBT against esketamine plus usual care in 93 patients with major depression and suicidal ideation. Its primary aim was feasibility, which it met. On secondary measures at week 18 the CBT group showed greater improvement in suicidal ideation and depression ratings. Secondary outcomes in a feasibility trial are a hint, not a verdict, but the hint points the same way as everything else here.
Summary of where the evidence stands
| Condition | Combination evidence | How confident |
|---|---|---|
| OCD | Infusions alone fade within about a week; sustained weeks to months with ERP | Strongest of the three |
| Depression | Open-label study suggested median relapse at 12 weeks vs 17 to 24 days; the randomised follow-up did not meet its primary outcome, though effect size was moderate and self-report favoured CBT | Mixed and unresolved |
| PTSD | Strong evidence for infusions alone; combination work still open-label | Promising, early |
What this means for how you plan treatment
If the window argument is even approximately right, then the decisions that matter are not only about dosing. They are about sequencing.
Have your therapist lined up before you start
This is the single most practical thing in this article.
Finding a therapist takes weeks in Connecticut. Finding one with a specific skill, such as ERP for OCD or a trauma-focused modality, can take longer. If you begin looking after your first infusion, you will spend the most useful period of your treatment on a waiting list.
In the Yale protocol, therapy began 24 to 48 hours after the first infusion. Whether or not that exact timing matters, the principle is that the therapy was already in place.
Keep your prescriber involved
Ketamine sits alongside your existing care rather than replacing it. Your psychiatrist or primary care physician should know you are having treatment, and should stay in the loop about how you are responding. Any decisions about your other medications belong with whoever prescribes them, not with us and not with an article.
Expect to feel able to do the work, not to have it done
The most common description I hear from responders is not euphoria. It is something closer to having room. Things that felt impossible feel merely difficult. That is exactly the state in which therapy tends to go somewhere, and it is also the state in which it is tempting to do nothing because you finally feel all right.
The people who hold their gains longest, in my experience, are the ones who treated feeling better as the start of the work rather than the end of it. That is an observation from practice rather than a trial result, and I will label it as such.
What we do and what we do not do
We are an infusion practice. We are not a therapy practice, and I think patients are owed that distinction clearly rather than discovering it later.
What that means in practice: we screen you, we treat you, we monitor you, and we coordinate with your therapist and prescriber. We do not provide the therapy itself, and we cannot be the only thing in your care plan. If you do not currently have a therapist, say so at the consultation and we will talk about what to look for, including the specific modality worth asking about for your condition.
A clinic that implies infusions alone are a complete treatment is making the sale easier and your outcome worse.
The honest counterargument
I should give the other side of this, because it exists.
Some people respond well to infusions with no concurrent therapy at all, and hold that response for months. That happens, and I have patients for whom it is true. It is also the case that the strongest trial of the combination in depression failed to meet its primary outcome, which is not a detail to bury.
There is a reasonable position that says: do the infusions, see what happens, add therapy if the response does not hold. I do not think that is wrong. My own view is that the cost of having therapy in place and not needing it is low, and the cost of needing it and not having it is a wasted window. But you are entitled to weigh that differently, and your own psychiatrist may have a view worth more than mine on your particular case.
Conclusion
The framing I would most like to replace is the one where the number of infusions is the whole treatment plan.
Six infusions with an engaged therapist, a psychiatrist in the loop and a plan for what happens afterward is a different treatment from six infusions alone, even though the invoice and the schedule look identical. The research is not strong enough for me to promise you a specific extra number of weeks of relief. It is more than strong enough to say that the window is worth filling.
If you are at the stage of planning this, do the unglamorous admin first. Find the therapist. Tell your prescriber. Then book the infusions.
It is not a requirement for treatment, and some people respond well without concurrent therapy. The evidence suggests the combination holds up better over time, most clearly in OCD, so we strongly encourage it and will coordinate with your therapist. We also need a prescriber or therapist involved in your wider care, which is separate from therapy sessions themselves.
It refers to a period after an infusion when the brain appears more able to form new connections. Much of the direct evidence comes from animal studies, and nobody can give you a reliable number of days for an individual person. Be sceptical of any clinic that quotes you a precise figure.
It depends on the condition. The depression studies used cognitive behavioural therapy. The OCD evidence specifically involves exposure and response prevention, which is a distinct skill worth asking a therapist about directly. PTSD work has used trauma-focused approaches including written exposure therapy. Your own clinician is the right person to decide which fits you.
In the Yale protocol, therapy began 24 to 48 hours after the first infusion and ran on separate days from the infusions. Whether that precise timing is necessary has not been established, but having therapy already underway rather than starting it later is the part that seems to matter.
It is mixed and I would rather say so. In OCD it is the clearest, with infusions alone fading within about a week and the combination sustained for weeks to months. In depression, a small open-label study was very encouraging and the randomised follow-up did not meet its primary outcome, despite a moderate effect size. In PTSD the combination work is still open-label.
Possibly, and that is the hope behind the whole approach, but it has not been demonstrated well enough for me to promise it. Boosters and therapy are better thought of as working together than as alternatives.
Mandatory Patient Safety and Driving Protocol
Because ketamine is a potent anesthetic that temporarily affects your reflexes, motor coordination, and visual perception, these rules are not optional. Our full preparation and recovery guide covers the rest.
- Pre-arranged transport required. You are prohibited from driving yourself home after an infusion. A responsible adult must accompany you and take you home. A rideshare on its own does not meet this requirement, and your driver is welcome to wait in our reception area.
- The 24-hour rule. Do not drive, operate machinery, or make significant legal or financial decisions for the remainder of the treatment day. You may resume driving the following calendar day after a full night of sleep.
- Do not schedule therapy for the same day as an infusion. You will not be in a state to do useful work, and the trial protocols deliberately kept them on separate days.
- Tell your therapist you are having infusions. Treatment can bring material to the surface, and your therapist should know rather than discover it mid-session.
- Strictly in-office. Use of ketamine outside our controlled clinical environment is unsafe and not permitted.
References
- Wilkinson ST et al. Cognitive behavior therapy may sustain antidepressant effects of intravenous ketamine in treatment-resistant depression. Psychotherapy and Psychosomatics, 2017;86:162-167. Open-label, 16 participants, four infusions over two weeks with CBT beginning 24 to 48 hours after the first infusion; median time to relapse around 12 weeks in responders, against 17 to 24 days in earlier relapse-prevention data.
- Wilkinson ST et al. Cognitive behavioral therapy to sustain the antidepressant effects of ketamine in treatment-resistant depression: a randomized clinical trial. Psychotherapy and Psychosomatics. Twenty-eight ketamine responders randomised to CBT or treatment as usual for 14 weeks; primary clinician-rated outcome not met, effect size d = 0.65, self-reported measure significantly favoured CBT.
- Efficacy and tolerability of ketamine in moderate to severe obsessive-compulsive disorder: a systematic review. Psychopharmacology, 2026. Effect generally fading within about a week as monotherapy, sustained for weeks to months when combined with exposure and response prevention.
- Feder A et al. A randomized controlled trial of repeated ketamine administration for chronic posttraumatic stress disorder. American Journal of Psychiatry, 2021. Six infusions over two weeks; 67 percent versus 20 percent response; median benefit roughly four weeks.
- Cognitive behavioral therapy following esketamine for major depression and suicidal ideation for relapse prevention: the CBT-ENDURE randomized trial. Journal of Clinical Psychiatry. Ninety-three participants; feasibility primary outcome met, with secondary measures at week 18 favouring the CBT group.
- Murrough JW et al. Rapid and longer-term antidepressant effects of repeated ketamine infusions in treatment-resistant major depression. Biological Psychiatry, 2013. Source for the six-infusion series and the 18-day median relapse figure referenced in related articles.
Is ketamine available at Ketamine Center of Connecticut?
Ketamine treatment is available at our two Connecticut locations:
232 Boston Post Rd Suite 13, Milford, CT 06460
1720 Post Rd E Suite 222, Westport, CT 06880
Treatments are strictly supervised by a board-certified physician, Dr. Gino Ang. Ketamine is prescribed only for adults with major depressive disorder who have not responded adequately to at least two different antidepressants. All treatment sessions are conducted in a controlled clinical environment, and Ketamine is administered under the physician’s direct supervision.
Patients must follow strict protocols:
- Ketamine is prescribed and monitored only by a qualified physician.
- Treatment is delivered in-office with continuous medical oversight.
- Use of ketamine outside this controlled setting is unsafe and not permitted.
If you are experiencing symptoms of depression and want to explore ketamine treatment, please contact us to schedule a consultation at our Milford or Westport clinic. All care is personalized to ensure safety, efficacy, and adherence to clinical guidelines.
Dr. Gino Ang MD
Board-Certified Anesthesiologist
Medical Review & Disclaimer
This content was reviewed for medical accuracy by Dr. Gino of the Ketamine Center of CT. This information is for educational purposes and is not a substitute for professional medical advice, diagnosis, or treatment. Use of this site does not establish a doctor-patient relationship.
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