Racemic Ketamine IV (Off-Label for Depression)

What it treats

Ketamine is FDA-approved as a general anesthetic. Its use for depression is entirely off-label. Off-label means a purpose the label doesn't formally list even though evidence and practice support it.

Off-label uses in mental health include:

• Treatment-resistant depression in adults.
• Depression with acute suicidal thoughts.
• Some anxiety and PTSD presentations, with weaker evidence.

For the FDA-approved intranasal S-enantiomer, see esketamine (Spravato).

How it works

Ketamine acts on the glutamate system, a different family of chemical messengers from the serotonin system that SSRIs target. It blocks NMDA glutamate receptors, which sets off downstream signaling changes that appear to strengthen synapses and shift mood within hours to days.

Because the pathway is different from SSRIs, ketamine can work when SSRIs haven't. And because the changes happen faster, some people notice a real mood shift after a single infusion. Ongoing dosing is usually needed to maintain the benefit.

Receptor mechanism (detail)

Racemic ketamine is a non-competitive NMDA receptor antagonist that contains both R- and S- enantiomers. NMDA blockade sets off downstream AMPA receptor activation, BDNF release, and mTOR signaling, which drive synaptic changes underlying the rapid antidepressant effect. R-ketamine is sometimes described as having less dissociative effect per unit of antidepressant action than the S-enantiomer, though this remains an active area of research.

Potency and typical dosing pattern

Ranges are typical framework only, not a prescription for any individual.

Standard antidepressant protocol (based on the APA/ASKP consensus and common clinic practice):

• Dose: 0.5 mg/kg IV over 40 minutes.
• Induction: two to three times weekly for two to three weeks (usually 6 infusions total).
• Maintenance: individualized. Some clinics extend to weekly, then every two weeks, then monthly, based on response.

Higher doses (up to 0.75 or 1 mg/kg) and different routes (intramuscular, subcutaneous) are used in some clinics with variable evidence.

Safety monitoring

• Vital signs every 5 to 10 minutes during and after the infusion. Ketamine typically raises blood pressure and heart rate.
• Dissociative symptom scale (CADSS or similar) tracked before and after.
• Blood pressure baseline and post-infusion, especially for people with hypertension.
• Bladder symptoms in longer-term or higher-frequency use (ketamine cystitis has been reported, mainly in chronic recreational users).
• Cognitive symptoms across a course of treatment.
• Misuse potential. Ketamine is a Schedule III controlled substance in the U.S.
• Contraindications include uncontrolled hypertension, unstable cardiovascular disease, and active psychosis.

What to expect

Common side effects

Common side effects (mostly during infusions) include:

• Dissociation, altered perception.
• Blood pressure rise.
• Heart rate rise.
• Dizziness.
• Nausea.
• Headache.
• Mild sedation.
• Vivid or unusual mental imagery.

Most side effects resolve within an hour after the infusion ends.

Serious side effects and warnings

Because ketamine isn't FDA-approved for depression, there is no boxed warning for that indication specifically. The anesthesia label does address risks. Serious problems reported with ketamine for mood use include:

• Blood pressure and heart rate rises, which can be marked. Uncontrolled hypertension is a contraindication.
• Dissociation intense enough to be distressing during infusion.
• Emergence phenomena (unusual thoughts or dreams) after infusion.
• Misuse potential. Ketamine is a Schedule III controlled substance.
• Bladder problems. Ulcerative or interstitial cystitis has been reported, mainly with chronic recreational use.
• Worsening of psychosis in patients with schizophrenia-spectrum illness.
• Effects on driving. No driving for the rest of the day.

Sexual side effects

Sexual side effects specifically from IV ketamine are not a prominent feature. If an SSRI or SNRI is still on board, sexual side effects from those drugs remain.

Weight, appetite, and sleep

Ketamine tends to be weight-neutral. Sleep may improve as depression improves.

Starting and dosing basics

This section is general background, not a dosing instruction for any individual. The plan is made by the prescriber and clinic team.

Ketamine for depression is given in clinics staffed to handle the effects, with an IV pump, monitors, and a clinician on hand. Patients arrive fasted per clinic protocol, sit or lie in a comfortable setting, and are monitored throughout. A ride home is required.

Missed doses and interactions

Missed sessions affect the treatment schedule; contact the clinic to reschedule.

Do not take sedatives, opioids, or alcohol on infusion days. Uncontrolled hypertension, unstable heart disease, active psychosis, and prior severe reaction to ketamine are contraindications or reasons for extra caution. Give every prescriber a full list of your medications and supplements, including over-the-counter ones.

Stopping and tapering

Ketamine infusions can be stopped without a taper. The benefit often fades once dosing stops, though the fade rate varies. Planning what comes next (continued oral antidepressant, ongoing psychotherapy, other maintenance approaches) is worth doing with the prescriber before ending a course.

Pregnancy and breastfeeding

This is an area where individual circumstances matter and the decision belongs with a clinician. Ketamine is generally avoided in pregnancy and breastfeeding when alternatives exist. Anyone who is pregnant, planning a pregnancy, or breastfeeding should talk it through with their prescriber so the specific risks and benefits can be weighed for their situation.

Cost and generic availability

Generic ketamine is inexpensive as a drug. The cost of a course comes mostly from the clinic staffing, monitoring, and IV administration. Insurance coverage for IV ketamine for depression is inconsistent; many patients pay out of pocket. Costs per infusion vary widely by region.

Common questions

How is IV ketamine different from Spravato (esketamine) nasal spray? Spravato is the FDA-approved S-enantiomer of ketamine, delivered as a nasal spray under a formal REMS program. Racemic ketamine IV is the older mix of both enantiomers, delivered intravenously, and used off-label. Both can help treatment-resistant depression; regulatory structure and delivery differ.

How fast does it work? Some people notice a real mood shift within hours of the first infusion. The typical assessment window is the induction course, two to three weeks.

Is it safe? In a properly staffed clinic with monitoring, the acute session risks (dissociation, blood pressure rise) are managed. Long-term risks with sustained use, particularly bladder and cognitive effects, are still being characterized.

Is it addictive? Ketamine has misuse potential and is a controlled substance. Under supervised clinic protocols the risk is low.

Can I drive after an infusion? No, not for the rest of the day. Plan for a ride.

Questions to ask your prescriber

• What's the clinic's protocol, and how is it monitored?
• What's the induction plan, and what does maintenance look like?
• What are the criteria for continuing versus stopping?
• What's the cost per session, and what does insurance cover?
• If we decide to stop it later, what's the plan for maintaining benefit?

Sources

This guide draws on current prescribing information and public health references and current as of June 8, 2026. It is reviewed for clinical accuracy and updated as guidance changes.

• U.S. Food and Drug Administration. Ketamine hydrochloride (Ketalar) prescribing information.
• American Psychiatric Association / ASKP consensus statement on the use of ketamine in mood disorders (2017 with subsequent updates).
• MedlinePlus, U.S. National Library of Medicine. Ketamine.
• American Society of Ketamine Physicians, Psychotherapists, and Practitioners (ASKP) clinical guidance.
• American Psychiatric Association. Practice Guideline for the Treatment of Patients with Major Depressive Disorder.