IM Ketamine in San Diego: How Intramuscular Ketamine Compares to IV Infusions

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.

What Is IM Ketamine?

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.

How IM Ketamine Compares to IV Ketamine: Side-by-Side

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.

Who Is IM Ketamine Best Suited For?

IM ketamine is often the preferred route in several specific situations:

Needle and IV Anxiety

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.

Difficult Venous Access

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.

Ketamine-Assisted Psychotherapy Settings

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.

Patient Preference Based on Prior Experience

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.

The IM Ketamine Experience

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.

What Conditions Is IM Ketamine Used For?

IM ketamine at Seaside Ketamine can be used for the same conditions as IV ketamine, including:

• Treatment-resistant depression
• Anxiety disorders
• PTSD and trauma
• Burnout and existential distress
• OCD
• Chronic pain (IV is often preferred for pain protocols, though IM is sometimes used)

Choosing Between IV and IM: How We Decide Together

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.