Medical ketamine is not a single treatment. Ketamine is an established prescription medicine for anaesthesia and selected pain-management uses, while ketamine treatment for depression is generally off-label in the UK. Esketamine nasal spray is licensed for certain adults with treatment-resistant depression, but NICE does not currently recommend it for routine NHS use. The defining features of medical treatment are a regulated product, clinical assessment, responsible prescribing and monitoring — not simply the presence of ketamine.
Ketamine has been used in medicine for decades, particularly as an anaesthetic and pain-relieving drug. More recently, it has attracted attention for a very different reason: its potential role in treating severe depression that has not responded to conventional therapies.
Those uses are not interchangeable. Ketamine given during an operation, ketamine used in specialist pain care, intravenous ketamine offered off-label for depression and licensed esketamine nasal spray all sit within different clinical and regulatory contexts.
That distinction matters because the phrase “ketamine treatment” can make several very different types of care sound like the same thing. They are not. The drug, formulation, indication, route of administration, monitoring requirements and evidence base can all differ.
In the UK, ketamine hydrochloride remains an authorised prescription-only medicine for anaesthesia and related clinical uses. Esketamine nasal spray is separately licensed for certain adults with treatment-resistant depression, although NICE does not currently recommend it for routine NHS treatment of that condition.
Medical ketamine at a glance
| Use or treatment | Current UK position |
|---|---|
| Anaesthesia | Established licensed medical use |
| Pain management | Used in selected clinical settings |
| Ketamine for depression | Ketamine itself is not licensed for depression; some specialist services may use it off-label |
| Esketamine nasal spray | Licensed for certain adults with treatment-resistant depression |
| Routine NHS esketamine for treatment-resistant depression | Not currently recommended by NICE |
| Self-treatment with unregulated ketamine | Not equivalent to medical treatment and carries different risks |
What is medical ketamine?
Medical ketamine is a regulated medicine used by healthcare professionals for recognised clinical purposes.
UK product information lists ketamine hydrochloride as a prescription-only medicine supplied as a solution for injection or infusion. Current authorised products include preparations containing 10 mg/ml or 50 mg/ml of ketamine. The exact formulation and concentration are documented by the manufacturer. See the electronic Medicines Compendium listing for ketamine hydrochloride medicines.
That level of certainty is one of the main differences between medical ketamine and a substance obtained outside regulated healthcare. In a clinical setting, the prescriber and treatment team know what drug is being administered, how much it contains and why it is being used.
For a broader explanation of formulations and terminology, see our Forms of Ketamine guide.
What is ketamine used for in anaesthesia?
Anaesthesia remains one of ketamine’s established medical uses.
UK prescribing information for ketamine hydrochloride states that it can be used as an anaesthetic agent for diagnostic and surgical procedures in adults and children. Some products are also indicated for induction of anaesthesia before other general anaesthetic agents are used. See the ketamine 50 mg/ml Summary of Product Characteristics.
Ketamine is useful in anaesthesia because it produces a dissociative state while also providing analgesic effects. Its clinical profile differs from many conventional sedatives, which is one reason it continues to have an important role in emergency and procedural medicine.
The important point for readers is that this use takes place within a monitored healthcare environment. It should not be confused with non-medical ketamine use simply because the active drug is the same.
Is ketamine used for pain?
Yes. Ketamine has analgesic properties and is used in selected pain-management settings.
The exact role varies according to the clinical situation. It may be used as part of anaesthesia, during painful procedures or, in specialist care, for difficult-to-manage pain where conventional approaches have not been sufficient.
That does not mean ketamine is a routine first-line painkiller. Its effects on consciousness, blood pressure, perception and other systems mean clinicians consider the wider medical picture before deciding whether it is appropriate.
Someone considering ketamine because of chronic pain should therefore approach it as a specialist medical question rather than assuming that evidence from anaesthesia or emergency medicine applies directly to long-term self-treatment.
Why is ketamine being studied for depression?
Ketamine attracted psychiatric interest because antidepressant effects have been observed through a mechanism that differs from conventional antidepressants.
Most commonly used antidepressants act primarily through serotonin, noradrenaline or related pathways. Ketamine has a strong effect on NMDA receptors and glutamate signalling, which has led researchers to study whether it may help people whose depression has not improved with standard treatments.
The evidence has been particularly important in treatment-resistant depression, where patients have already tried more than one conventional treatment without adequate benefit.
However, promising research does not automatically mean a drug is licensed, routinely recommended or suitable for every person with depression.
Is ketamine licensed for depression in the UK?
Ketamine itself is not currently licensed in the UK for treating depression.
NICE’s January 2026 surveillance review states that ketamine is approved by the MHRA as an anaesthetic drug but is not currently approved for treating depression. It also notes that guidance on repeated intravenous ketamine for treatment-resistant depression remains limited and that the quality of evidence varies. See the January 2026 NICE surveillance review.
This means that when a UK clinician uses ketamine specifically for depression, that use is generally described as off-label.
Off-label prescribing is not the same as illegal prescribing. It means the medicine is being used outside the indication covered by its marketing authorisation. The clinician remains responsible for deciding whether that use is appropriate for the individual patient.
What does off-label ketamine treatment mean?
Off-label treatment means a licensed medicine is being prescribed for a condition, dose, route or patient group that is not included in its authorised product licence.
Doctors can prescribe medicines off-label in appropriate circumstances, but the decision usually requires a clearer clinical justification because the manufacturer has not obtained a marketing authorisation for that specific use.
For ketamine and depression, this distinction is particularly important. A private clinic offering ketamine infusions for depression may be providing a legitimate medical service, but the treatment is not the same thing as a licensed antidepressant indication for ketamine itself.
Patients should therefore understand what is being offered, what evidence supports it, whether the use is licensed or off-label, who is responsible for prescribing and how treatment is monitored.
What is esketamine?
Esketamine is the S-enantiomer of ketamine, one of the two mirror-image forms of the ketamine molecule.
Unlike ketamine itself, esketamine nasal spray has a specific UK marketing authorisation for treatment-resistant major depressive disorder in certain adults.
The authorised product is Spravato, which contains esketamine hydrochloride. Each single-use nasal spray device contains the equivalent of 28 mg of esketamine. See the Spravato Summary of Product Characteristics.
The licensed indication is for adults whose current moderate-to-severe depressive episode has not responded to at least two different antidepressant treatments. It is used together with an SSRI or SNRI rather than as a stand-alone treatment. NICE describes the authorised indication in its esketamine technology appraisal.
Is Spravato available on the NHS?
Esketamine nasal spray is licensed in the UK, but NICE does not currently recommend it for routine NHS treatment of treatment-resistant depression.
NICE concluded that there was substantial uncertainty around the clinical evidence, treatment pathway, longer-term effects and cost effectiveness. Its current depression guideline therefore states that esketamine nasal spray is not recommended for treatment-resistant depression. See NICE guidance on treatment-resistant depression.
NICE reviewed whether the appraisal needed updating and decided that the recommendation should remain unchanged because newer evidence did not sufficiently resolve the existing uncertainties. See the NICE review decision.
This is an important distinction: a medicine can hold a UK marketing authorisation without being recommended by NICE for routine NHS commissioning.
How is esketamine treatment given?
Spravato is administered as a nasal spray in a healthcare setting rather than being taken home and used without supervision.
The treatment involves clinical monitoring because esketamine can cause sedation, dissociation, increases in blood pressure and other effects that need to be assessed before a patient leaves.
The product also has dedicated risk-minimisation materials for healthcare professionals and patients. These include guidance on monitoring and a readiness-to-leave checklist. The electronic Medicines Compendium publishes the current Spravato risk-management materials.
This is another example of why medically supervised treatment cannot be judged simply by comparing the drug name with ketamine sold outside healthcare.
What is a ketamine infusion?
A ketamine infusion usually refers to ketamine delivered intravenously over a controlled period in a clinical setting.
In anaesthesia and some pain settings, intravenous ketamine is an established medical route. In psychiatry, intravenous ketamine may also be offered by specialist services for treatment-resistant depression, but this is generally an off-label use in the UK.
The term “infusion” does not by itself tell you the clinical purpose, treatment protocol or quality of the service. A hospital anaesthetic infusion and a private psychiatric ketamine programme can involve the same medicine but exist within very different treatment pathways.
Readers considering a private service should therefore look beyond the word “ketamine” and ask what condition is being treated, who is prescribing, what assessment takes place beforehand and what medical supervision is available.
What is ketamine-assisted psychotherapy?
Ketamine-assisted psychotherapy is a broad term used for treatment models that combine ketamine administration with psychological therapy.
There is no single universal protocol behind the phrase. Clinics can differ in the formulation used, route of administration, timing of therapy, professional roles and patient-selection criteria.
That makes it important not to assume that every service using the same label is offering the same intervention or working from the same evidence base.
The role of psychotherapy alongside ketamine remains an area of clinical interest, but anyone considering treatment should ask how the psychological component is delivered and what evidence supports the clinic’s particular approach.
Medical ketamine, esketamine and unregulated ketamine: key differences
| Type | What it means | UK status |
|---|---|---|
| Ketamine for anaesthesia | Regulated ketamine hydrochloride used by healthcare professionals | Licensed medical use |
| Ketamine for pain | Use within specialist clinical care | Depends on indication and setting |
| Ketamine for depression | Usually intravenous or otherwise medically administered ketamine | Generally off-label |
| Esketamine nasal spray | Licensed S-ketamine medicine used with an antidepressant | Licensed for treatment-resistant depression, but not routinely recommended by NICE for NHS use |
| Unregulated ketamine | Substance obtained outside legitimate medical supply | Not equivalent to medical treatment |
What happens before medical ketamine treatment?
A reputable medical service should assess whether ketamine is appropriate before treatment begins.
The exact process depends on the indication, but it may include reviewing psychiatric or medical history, current medicines, previous treatments, cardiovascular health, substance use and other factors that could affect risk.
For depression treatment, the assessment should also establish whether the person actually meets the service’s criteria for treatment-resistant illness and whether other evidence-based options have been adequately considered.
The assessment matters because ketamine is not simply a stronger version of a conventional antidepressant. It has different effects, different monitoring requirements and a different risk profile.
What monitoring is needed during treatment?
Monitoring depends on the medicine and route used, but medically supervised ketamine or esketamine treatment should not be treated as a casual appointment.
Blood pressure, level of sedation, dissociation and general clinical condition may need to be observed. With esketamine nasal spray, the product information requires administration under direct supervision and post-dose monitoring.
NICE has also noted that esketamine treatment carries a greater practical burden than ordinary oral antidepressants because patients may need repeated clinic visits and observation after administration.
A clinic should be able to explain what happens if someone becomes excessively sedated, develops significant blood-pressure changes or experiences another adverse effect.
What are the side effects of medical ketamine?
Medical supervision reduces uncertainty but does not make ketamine free from side effects.
Possible effects can include dissociation, dizziness, nausea, changes in blood pressure, altered perception and sedation. The exact profile depends on the medicine, route and clinical context.
Spravato product information also lists dissociation and sedation among the adverse effects that require particular attention. See the current prescribing information for esketamine nasal spray.
Longer-term concerns also matter when exposure becomes repeated. Our Ketamine Safety and Harm Reduction pillar covers bladder, urinary, abdominal, liver and dependence-related risks in more detail.
How is medical treatment different from self-treating depression with ketamine?
The difference is much greater than simply knowing how much ketamine someone intends to take.
Medical treatment involves diagnosis, assessment, a known pharmaceutical product, clinical responsibility and monitoring. Self-treatment with an unregulated substance lacks those safeguards and may also involve uncertainty about identity or concentration.
It can also delay appropriate care if a person assumes that because ketamine is being researched for depression, any ketamine use has the same therapeutic effect.
It does not.
Clinical evidence applies to particular treatments, patient groups, formulations and protocols. It should not be automatically transferred to an unknown product used without medical supervision.
Are private ketamine clinics legal in the UK?
Private clinics can legally provide ketamine treatment where the service is properly run and the medicine is prescribed by an appropriate healthcare professional.
However, legality alone does not tell you whether a particular clinic is suitable for a particular patient.
Anyone considering a private ketamine service should look at who is responsible for prescribing, what qualifications the clinical team holds, how the patient is assessed, whether the proposed use is licensed or off-label, what monitoring occurs and what happens if complications develop.
A service should also be transparent about evidence and limitations rather than presenting ketamine as a guaranteed or universally appropriate treatment.
What should you ask a ketamine clinic?
A useful conversation with a clinic should cover more than price and appointment availability.
- Who assesses whether treatment is appropriate?
- Who prescribes the medicine?
- Is the proposed use licensed or off-label?
- What formulation and route are used?
- What happens during monitoring?
- How are adverse effects handled?
- How is progress assessed?
- What happens if treatment does not help?
- How does the clinic communicate with the patient’s GP or existing mental health team?
Clear answers do not guarantee that a treatment is right for someone, but vague answers to basic clinical questions are a reason to look more carefully.
Can you get ketamine treatment through the NHS?
The answer depends on what ketamine is being used to treat.
Ketamine remains part of NHS medical practice as an anaesthetic and can also be used in other specialist clinical contexts.
The situation is different for depression. Ketamine itself is not licensed for depression, and NICE does not currently recommend esketamine nasal spray for routine NHS treatment of treatment-resistant depression.
That does not mean ketamine-related psychiatric treatment never occurs within UK healthcare. Specialist or research services may operate under specific arrangements, but access is not equivalent to having a routinely commissioned national NHS treatment pathway.
Is medical ketamine safer than unregulated ketamine?
Medical ketamine removes several important uncertainties because the product, concentration, indication and clinical environment are known.
That does not make the drug risk-free.
A more accurate way to describe the difference is that medical use allows risk to be assessed, monitored and managed. With an unregulated product, the substance itself may be uncertain before the pharmacological risks are even considered.
This is why our Buy Ketamine Online UK: Risks, Legality and What to Know page focuses on product uncertainty and legal context rather than treating online supply as an alternative treatment route.
What is the current state of the evidence?
Ketamine and esketamine are both important areas of psychiatric research, but the evidence is not as simple as saying that ketamine “works for depression”.
Studies have reported antidepressant effects, particularly in treatment-resistant depression, but questions remain around long-term outcomes, treatment schedules, relapse, patient selection and how repeated treatment should be integrated into ordinary mental health care.
NICE’s 2026 surveillance work specifically noted continuing uncertainty around repeated intravenous ketamine and the translation of research findings into clinical practice.
That does not erase the evidence of benefit. It explains why regulators, clinicians and guideline bodies can accept that a treatment shows promise while still being cautious about routine use.
What is the most important distinction?
“Medical ketamine” describes a clinical process, not merely possession of the same chemical.
The process includes a legitimate medicine, an appropriate indication, a prescriber who takes responsibility for the treatment, an assessment of whether the patient is suitable and a plan for monitoring both benefit and harm.
That is why licensed anaesthetic ketamine, off-label ketamine treatment for depression, licensed esketamine nasal spray and unregulated ketamine should not be collapsed into one category simply because they share related chemistry.
References
- Advisory Council on the Misuse of Drugs: Ketamine – updated review of use and harms
- electronic Medicines Compendium: ketamine hydrochloride medicines
- Ketamine 50 mg/ml Injection: Summary of Product Characteristics
- Spravato 28 mg nasal spray: Summary of Product Characteristics
- Spravato risk-minimisation materials
- NICE: Information about esketamine for treatment-resistant depression
- NICE: Depression in adults – treatment and management
- NICE: Review decision for esketamine nasal spray
Evidence last checked: 18 September 2026
