At a Glance : Intramuscular (IM) ketamine therapy delivers powerful therapeutic benefits without requiring an IV line. This fast, single-injection method provides highly reliable medication absorption to rapidly relieve severe depression, anxiety, and PTSD while maintaining rigorous clinical safety standards and continuous medical monitoring.
When people research ketamine therapy, most of the information they find focuses on intravenous (IV) infusions — and for good reason. IV ketamine has the largest evidence base and the most precise dosing control available. But it’s not the only delivery method, and for some patients, intramuscular (IM) ketamine may be an equally effective and more appropriate fit.
At Seaside Ketamine, we offer both IV ketamine infusions and IM ketamine, selected based on each patient’s clinical needs, history, comfort level, and treatment goals.
Intramuscular ketamine is administered via injection into muscle tissue — typically the deltoid (shoulder) or gluteal muscles. From there, ketamine is absorbed into the bloodstream over a slightly different time curve than IV delivery. The therapeutic experience is similar to IV ketamine but with a somewhat slower onset and slightly different absorption profile.
| IV Ketamine | IM Ketamine | |
|---|---|---|
| Onset | 1–2 minutes | 5–15 minutes |
| Duration of experience | 40–60 minutes | 45–75 minutes |
| Dose precision | Very precise — continuously titrated | Precise — calculated at time of injection |
| Real-time adjustment | Yes — can increase or decrease mid-session | No — dose is set at injection |
| Access requirement | IV catheter placement | No IV required |
| Experience quality | Immersive, adjustable | Immersive, slightly more gradual onset |
The primary clinical difference is that IV allows real-time dose adjustment throughout the session, while IM sets the dose at the time of administration. For experienced clinicians like Dr. Gillin, this is fully manageable through careful pre-session assessment and weight-based dose calculation.
IM ketamine is often the preferred route in several specific situations:
Some patients have significant anxiety around IV placement or needle insertions in general — particularly around catheters, blood draws, or anything involving a vein. For these individuals, a quick intramuscular injection (more like a vaccine than an IV) can meaningfully reduce pre-session anxiety that might otherwise interfere with the therapeutic experience itself.
Some patients have veins that are small, fragile, or difficult to cannulate reliably — a common issue for older patients, those with a history of IV drug use, or those who have had repeated medical procedures. IM administration sidesteps this challenge entirely.
In KAP contexts where the emphasis is on the psychological and experiential component of treatment, IM ketamine is widely used and well-validated. Many of the foundational KAP protocols — including those developed with MDMA-assisted therapy researchers in adjacent psychedelic medicine contexts — use IM administration.
Some patients who have experienced both simply prefer the slightly different quality of the IM experience — the marginally slower onset, the slightly different arc of the experience. Individual variation is real and worth accounting for.
Many patients describe the IM ketamine experience as comparable in depth and quality to IV — immersive, disorienting in a meaningful way, and with the same potential for profoundly healing psychological experiences when properly set and supported. The slightly slower onset is something some patients find more comfortable and less startling than IV’s near-immediate effect.
As with all ketamine delivery at Seaside Ketamine, we provide careful monitoring throughout the session including vital sign assessment, and patients remain at the clinic until they are alert, stable, and have a confirmed plan for safe transportation home.
IM ketamine at Seaside Ketamine can be used for the same conditions as IV ketamine, including:
The route of administration is one of many personalized decisions Dr. Gillin will guide during your initial evaluation. The most important factors are your clinical history, your goals, your comfort with the process, and any practical constraints. In many cases, the choice comes down to what will create the most effective and comfortable therapeutic experience for you as an individual.
There is no universally superior option — there is the right option for you. We’ll figure that out together.
While both methods deliver highly effective relief for treatment-resistant conditions, IV ketamine provides continuous, adjustable dosing through an intravenous drip. Conversely, IM ketamine uses a single intramuscular injection, offering a simpler experience for the remainder of your session while maintaining a robust 93% bioavailability.
Yes. Because our medical team administers it as a single injection, IM ketamine typically reaches its peak concentration slightly faster than the gradual onset of an IV drip. This slightly more intense, rapid peak often provides an optimal window for patients engaging in Ketamine-Assisted Psychotherapy (KAP).
IM ketamine is an excellent option for patients who experience severe depression, anxiety, or PTSD but feel uncomfortable with IV lines or have difficult venous access. It provides the exact same medical oversight and therapeutic outcomes as IV treatments without continuous catheter placement.
