Zadaka Health · Colorado
Understanding
Ketamine Therapy
A comprehensive guide to how ketamine works, what the research shows, the real benefits and risks — and how medically supervised care makes all the difference.
A comprehensive guide to how ketamine works, what the research shows, the real benefits and risks — and how medically supervised care makes all the difference.
Ketamine has been used in medicine since 1970, when the FDA approved it as a general anesthetic. It appears on the WHO's List of Essential Medicines and has been used safely in emergency rooms and surgical suites for decades.
In recent years, groundbreaking research revealed ketamine's remarkable potential for mental health — particularly for people who haven't found relief with traditional antidepressants. Unlike conventional antidepressants that take weeks to work, ketamine often produces meaningful changes within hours.
At Zadaka Health, ketamine therapy refers to the medical clearance, preparation, and integration surrounding your experience — not the infusion itself, which is administered at partnering licensed clinics.
Ketamine infusion therapy for depression, anxiety, and PTSD is currently off-label — meaning it is legally prescribed and administered but not yet FDA-approved for these uses (except intranasal esketamine/Spravato for treatment-resistant depression, approved 2019). Off-label use is common and does not mean unsafe; it means the research is ongoing and promising.
Ketamine significantly boosts Brain-Derived Neurotrophic Factor — a protein that promotes the growth and reconnection of neurons. Chronic depression is associated with loss of neuronal connectivity; ketamine appears to reverse this, essentially "regrowing" pathways that depression has worn away.
The default mode network is responsible for ruminative, self-referential thinking — the "loop" of negative thoughts common in depression. Ketamine temporarily quiets this network, creating a window of cognitive flexibility and a loosening of rigid mental patterns.
Unlike SSRIs, which target serotonin, ketamine works by blocking NMDA receptors for glutamate — a neurotransmitter linked to brain excitotoxicity. This entirely different mechanism is why ketamine can work for people who haven't responded to conventional antidepressants.
This short video from the National Institute of Mental Health (NIMH) — the US government's leading mental health research agency — explains how ketamine-derived esketamine works for treatment-resistant depression, featuring real patient experiences and the scientists behind the research. Clear, credible, and under 3 minutes.
Understanding the science behind ketamine helps you make an informed decision and get more out of the experience. Preparation is not just helpful — it's a clinical best practice.
Produced by the National Institute of Mental Health (NIMH) — a division of the US National Institutes of Health. Click to watch on YouTube.
Many patients report meaningful reduction in depression, anxiety, or suicidal ideation within hours — a stark contrast to the 6–8 week wait for SSRIs.
Studies consistently show ~70% response rates in patients who have failed multiple antidepressant trials — people who had run out of options.
The brain becomes more flexible and receptive following ketamine. This "open window" is when preparation and integration work can produce the most lasting change.
Some of the most compelling research shows ketamine can rapidly reduce suicidal thoughts — a clinical need no conventional antidepressant addresses quickly.
The dissociative experience can produce meaningful psychological shifts and emotional access that accelerate therapeutic work when properly supported.
Over 50 years of clinical use as an anesthetic provides a robust safety record under appropriate medical supervision.
Ketamine produces a temporary altered state — perceptual changes, detachment, and time distortion. Proper preparation makes a significant difference in how this is experienced.
Without ongoing support, benefits may fade within days to weeks. Integration — what Zadaka Health specializes in — turns a temporary shift into lasting change.
Contraindicated in active psychosis, uncontrolled hypertension, certain cardiac conditions, a history of ketamine misuse, and pregnancy. A thorough medical evaluation is essential.
Ketamine carries a risk of psychological dependence if used outside clinical supervision. Responsible protocols include spacing sessions appropriately and monitoring for dependence patterns.
Common during and immediately after treatment. Cardiovascular monitoring and antiemetics address these in supervised settings.
No two ketamine experiences are alike. Some surface difficult material. Preparation helps you approach this with equanimity rather than fear.
The evidence base for ketamine in mental health is growing rapidly. Here are the key findings that inform evidence-based ketamine care.
The largest depression study ever conducted found that the majority of patients do not achieve significant benefit from antidepressant medications — and with each failed trial, the odds of success decline further. This is the clinical reality that makes ketamine's response rates so significant.
Rush et al., STAR*D Study, NEJM 2006
Multiple studies confirm that ketamine produces antidepressant effects within hours that are equal to or greater than standard antidepressants. Former NIMH Director Tom Insel called it "the most important breakthrough in antidepressant treatment in decades." This rapid action is particularly critical for patients experiencing suicidal ideation.
Insel, NIMH; Murrough et al., Biol Psychiatry 2013
Across multiple controlled trials, IV ketamine consistently demonstrates meaningful symptom reduction in roughly 70% of patients with treatment-resistant depression — a population that had exhausted other options. No antidepressant has previously achieved this level of efficacy in this population.
Aan Het Rot et al., 2010; Murrough et al. 2013
A landmark 2019 study using Ketamine-Assisted Psychotherapy reported significant decreases in both depression and anxiety, with outcomes surpassing ketamine alone. Preparation and integration — not just the medicine — determine the depth and durability of change.
Dore et al., Journal of Psychoactive Drugs, 2019
A 2024 clinical review found significant ketamine-associated reductions in anxiety across generalized and social anxiety disorder, with some studies showing 50% or greater symptom reduction. Patients who responded maintained remission for over three months with appropriate maintenance care.
Innerbloom Ketamine Therapy, 2024 Review; Glue et al. 2017
Research shows ketamine's first and most dramatic effect is often a rapid, significant reduction in suicidal ideation — a critical need no conventional antidepressant addresses quickly. This alone makes medically supervised ketamine a potentially life-saving intervention.
Murrough et al.; Grunebaum et al., Bipolar Disorders 2017
A plain-language walkthrough of the neurological mechanisms behind ketamine — from glutamate blockade to BDNF release — and why these effects are so clinically significant for people who haven't found relief through conventional treatments.
Read MoreThe ketamine session itself is just a few hours. What you do in the days and weeks after — how you process, reflect, and translate insight into life — is what determines whether those hours produce lasting change or fade.
Read MoreAn honest, evidence-based comparison — including what the STAR*D study revealed about medication response rates, and why ketamine's mechanism and speed represent a genuine clinical breakthrough.
Read More
MSN, APRN, FNP-C · Founder, Zadaka Health
Leor Zadaka is a board-certified Family Nurse Practitioner who founded Zadaka Health around a simple but rarely fulfilled promise: that people navigating ketamine therapy and natural medicine deserve both exceptional clinical care and genuine human connection.
Leor earned his MSN from Georgetown University with a, with additional training in psychopharmacology from the Neuroscience Education Institute. Before founding this practice, he built a career across healthcare's most demanding environments — oncology, end-of-life care, emergency medicine, and dedicated ketamine therapy clinics. These experiences didn't just sharpen his clinical instincts; they deepened his understanding of what people actually need when they're going through something hard.
Outside the clinic, Leor is a devoted dog dad, an avid hiker, and someone who finds deep meaning in connection with people and the Colorado outdoors. His patients consistently describe him as someone who makes them feel genuinely heard — not because it's a technique, but because it's who he is.
No. Zadaka Health specializes in medical clearance, preparation, and integration — the clinical pieces that determine whether your experience is safe and meaningful. Ketamine infusions are administered at partnering licensed clinics. Leor refers clients to appropriate providers and coordinates care throughout.
Candidacy is determined through a comprehensive medical and psychiatric evaluation — which is exactly what Zadaka Health provides. Good candidates typically include people with treatment-resistant depression, anxiety, PTSD, or trauma who haven't found adequate relief through conventional treatments. A free consultation is the best first step.
Ketamine produces a dissociative state that can surface unexpected emotions and psychological material. How you enter that experience — your mindset, intentions, and sense of safety — profoundly shapes what emerges and how you relate to it. Preparation builds the internal conditions that allow the medicine to work with you, not against you.
Without integration, the benefits of ketamine tend to fade within days to weeks. The neuroplasticity window opened by ketamine is an opportunity — but insight without action rarely produces lasting change. Integration is what transforms a profound experience into a different way of living.
Zadaka Health is a private pay practice. Ketamine infusions are typically not covered given their off-label status; intranasal esketamine (Spravato) may have some coverage for qualifying patients. A superbill can be provided for potential out-of-network reimbursement.
Ketamine has a known potential for psychological dependence with frequent recreational use. Within a supervised clinical protocol with appropriate spacing, this risk is significantly reduced. Zadaka Health's evaluation specifically screens for substance use history and contraindications — and transparency about your history is always welcome.
A free, no-obligation consultation with Leor is the best way to understand whether ketamine therapy is right for you — and how Zadaka Health's approach is different from what you'll find elsewhere.
This page is for educational purposes only and does not constitute medical advice or a provider-patient relationship. Zadaka Health provides medical evaluation, preparation, and integration only — IV ketamine is administered at separately licensed facilities. Natural medicine facilitation is provided under Colorado's Natural Medicine Health Act. Individual results vary. If you are in a mental health crisis, please call 988 or 911.
