Who Is Not a Good Candidate for Ketamine Therapy?

Most adults with treatment-resistant depression, anxiety, or PTSD are medically cleared for ketamine therapy after a standard screening. But a handful of conditions make ketamine genuinely unsafe rather than merely something to discuss with a doctor, and knowing the difference upfront saves everyone time. This article lays out the absolute exclusions, the conditions that call for a closer look rather than an automatic no, and what a real screening process actually checks.

Absolute contraindications: who genuinely should not receive ketamine

Uncontrolled hypertension and significant cardiovascular disease

Ketamine’s sympathomimetic effects mean it can raise blood pressure and heart rate. In someone with uncontrolled hypertension, a recent heart attack, unstable angina, severe heart failure, or a known aortic aneurysm, that spike carries a real risk of a dangerous cardiovascular event. Controlled hypertension managed with medication is a different situation and generally does not disqualify a candidate on its own.

Active psychosis or schizophrenia

Ketamine’s dissociative effects can worsen symptoms in someone experiencing active psychosis, which is why this is treated as an absolute exclusion rather than a caution.

Active mania or untreated bipolar I disorder

During a manic episode, a person cannot safely engage with the structured, reflective process that makes ketamine therapy work. Stable bipolar disorder, by contrast, is generally evaluated case by case rather than automatically excluded.

Recent heart attack or stroke, and severe liver disease

These conditions affect how the body handles the cardiovascular and metabolic demands of ketamine, and are treated as firm exclusions until they are resolved or well past the acute phase.

Pregnancy and breastfeeding

Ketamine is not recommended during pregnancy or while breastfeeding due to potential risks to a developing fetus or infant.

Active substance use disorder involving ketamine or other dissociatives

A current, active substance use disorder involving ketamine, PCP, or similar dissociative substances is an exclusion, both for safety and because it undermines the therapeutic structure the treatment relies on. A substance use history that is not active and not involving these specific substances is evaluated individually.

A known ketamine allergy

Documented hypersensitivity or allergy to ketamine or its components is an absolute exclusion. True allergic reactions are rare but are taken seriously when reported.

Conditions that call for a closer look, not an automatic no

• Well-controlled bipolar II disorder on a stable mood regimen
• Mild or well-managed hypertension, confirmed with current readings
• A substance use history in documented, stable remission, unrelated to ketamine or other dissociatives
• Mild liver impairment that does not meet the threshold for severe disease
• A history of seizures or elevated intracranial pressure, where modern evidence has actually softened older assumptions, though screening still applies

The distinction matters because a condition landing in this category means a more thorough intake conversation, not an automatic disqualification, so it is worth having that conversation rather than assuming you are ruled out.

What screening actually checks

A real intake for ketamine therapy at Village TMS includes a full medical history, current medications, psychiatric history, and a baseline blood pressure and cardiovascular review, along with a conversation about your goals for treatment. This is what allows a provider to tell most applicants they are cleared to start, rather than defaulting to caution across the board.

If you are screened out, what comes next

Being ruled out for ketamine therapy is not the end of the road. Depending on the specific reason, alternatives such as TMS or Spravato may be appropriate, since each carries a different risk profile and different screening requirements. A genuine evaluation should always include a conversation about what else is available if ketamine is not the right fit.