One injection into a muscle. Most of the appointment is the careful part around it.
Table of Contents
- What Intramuscular Ketamine Means
- Why the Route Matters
- Before Your First Session
- What Happens During a Session
- The Rest of the Day
- How Many Sessions It Takes
- FAQs About Intramuscular Ketamine
Most people who ask about ketamine have already tried several antidepressants. What they want to know is simple. What actually happens in the room?
The answer is less dramatic than the word ketamine suggests. You sit in a reclining chair, receive a single injection, and rest while the effects rise and fade under observation. The whole visit is built around monitoring.
This guide walks through intramuscular (IM) ketamine from the first evaluation to the drive home you will not be making yourself.
What Intramuscular Ketamine Means
Intramuscular simply describes the route. The medication is injected into a large muscle rather than dripped into a vein through an IV line.
Ketamine has been an FDA-approved anesthetic since 1970, and the injectable form is labeled for both intravenous and intramuscular use, according to the FDA prescribing information for Ketalar. For depression it is used off-label. In an October 2023 compounding risk alert, the FDA stated that ketamine is not approved for the treatment of any psychiatric disorder, which means the dose, the schedule and the monitoring are set by the treating physician rather than by a label.
At Dr. Sambunaris & Associates, IM is the route Dr. Sambunaris uses for ketamine therapy in Alpharetta.
Why the Route Matters
How ketamine enters the body decides how much of it reaches the bloodstream.
A review in Pharmacological Reviews puts the bioavailability of an intramuscular dose at 93%, with peak blood levels reached within 5 to 30 minutes. Swallowed ketamine is a different story. Only 16% to 29% of an oral dose survives first-pass metabolism in the liver, and nasal ketamine sits around 45% to 50%.
In practical terms, IM delivers nearly the full dose without needing an IV line, and the effect arrives within minutes. That combination is the main practical argument for the route.
Before Your First Session
A proper evaluation comes before any treatment.
The American Psychiatric Association task force that published a consensus statement on ketamine for mood disorders recommends a pretreatment assessment that covers:
- A full diagnostic assessment, including any history of substance use or psychotic disorders
- A baseline measure of symptom severity, so later change can be tracked
- A documented history of every antidepressant tried, to confirm the earlier trials were adequate
- A review of physical health for risk factors, blood pressure among them
At our practice, candidacy is decided after a physical exam, a review of your medical history and a discussion of your symptoms. From there Dr. Sambunaris tailors the plan to you.
Bring a written list of every medication and supplement you take, with doses. Bring the antidepressants you have stopped as well. That list shapes the decision more than anything else you can prepare.
What Happens During a Session
Clinics differ in the details, but the structure is consistent.
Vital signs first. Blood pressure and pulse are checked before anything is given. Ketamine raises blood pressure for a while, so the starting number matters.
The injection. A single shot into a muscle, similar to a routine vaccine.
The effect. Within minutes, perception usually starts to shift. This is dissociation, which the FDA describes as a disconnection between a person’s thoughts, feelings, and sense of space, time, and self. It is expected, and it fades.
Observation. You stay seated while staff monitor you. In one published study of IM ketamine at US outpatient clinics (Ahuja et al., BMC Psychiatry, 2022), patients rested in a reclining chair in a quiet, dim room, wore eye shades, listened to calm instrumental music, and had blood pressure and pulse checked with direct observation for at least 60 minutes. A VA program kept patients for 120 minutes.
The quiet, dim room is deliberate. The ketamine label itself advises keeping verbal, touch and visual stimulation low to ease reactions during recovery.
You leave once the clinician is satisfied that you are steady and alert. Your care team will tell you what their own protocol looks like before your first session.
The Rest of the Day
Plan on someone else driving.
For esketamine nasal spray, the FDA label instructs patients not to drive or operate machinery until the next day after a restful sleep. The same caution is sensible after IM ketamine unless your clinician tells you otherwise. Arrange a ride before you arrive, not after.
Keep the rest of the day light. Avoid alcohol, big decisions and anything that needs full coordination. Some people feel tired or mildly nauseated afterward. Tell your care team if either lingers.
Note how you feel over the next few days, in writing. Mood, sleep and energy are all worth tracking. That record is useful at your next appointment, since depression tends to blur memory of how recent days actually went.
How Many Sessions It Takes
One session is rarely the whole plan.
The APA consensus statement describes the antidepressant effect of ketamine as rapid and robust, but often transient. It also notes that repeated dosing can extend the benefit for at least several weeks. Most published studies have looked at less than a month of treatment, and one randomized trial of IV ketamine found twice-weekly dosing about as effective as three times a week.
Real-world schedules look similar. In the VA study of 179 veterans, the induction course was eight IM treatments over four weeks. In the Ahuja outpatient study, the median was four treatments, and patients who continued with maintenance sessions kept an average improvement for more than seven months. That study was open-label with no control group, so its numbers are encouraging rather than conclusive.
What matters more than any average is the plan built for you. Frequency usually tapers as symptoms improve, and continuing depends on whether the benefit is clear.
FAQs About Intramuscular Ketamine
Will I be unconscious during IM ketamine? No. The doses used for depression are far lower than anesthetic doses, and the APA consensus statement notes that the standard depression dose does not produce general anesthetic effects. You remain awake, though perception changes for a while. The experience is often described as dreamlike or detached rather than asleep.
Does the injection hurt? It is a standard intramuscular injection, much like a vaccine. Most people feel a brief sting at the site. The part people tend to remember is the altered perception afterward, not the shot.
How quickly might I notice a difference? Ketamine is studied for depression partly because its effect can arrive quickly, while standard antidepressants commonly take weeks. Response varies from person to person, and it does not help everyone. Your clinician will track your symptoms across sessions rather than judging from one.
Can I keep taking my antidepressant? Often, yes, but that decision belongs to your psychiatrist. Some medications interact with ketamine or affect blood pressure. Never start, stop, or change a medication on your own around ketamine treatment.
Is IM ketamine the same as Spravato? No. Spravato is esketamine, a nasal spray containing one of the two mirror-image forms that make up ketamine, and it is FDA approved for treatment-resistant depression. IM ketamine uses the standard mixture of both forms and is off-label. The two are not interchangeable, and the right choice depends on your history.
Ask Whether IM Ketamine Fits Your Situation
If two or more antidepressants have not worked, it is worth a conversation. Start with our guide to treatment-resistant depression, then talk to us about whether ketamine belongs in your plan.
Dr. Sambunaris & Associates provides ketamine therapy in Alpharetta, Georgia.
Book My Consultation or call (770) 817-9200.
Reviewed by Angelo Sambunaris, M.D., with more than 20 years of clinical experience and over 30 years in clinical research.
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Medical Disclaimer: This article is for general educational purposes only and is not a substitute for professional medical advice, diagnosis, or treatment. Ketamine is not FDA approved for the treatment of depression or any other psychiatric disorder, and its use for these conditions is off-label. Reading this article does not create a doctor-patient relationship. Always talk to your doctor or another qualified health provider about your own situation, and never start, stop, or change medication without speaking to your prescriber. If you think you may be having a medical emergency, call 911.