Ketamine

What is ketamine?

Ketamine is a medication developed in the 1960s primarily as a dissociative anesthetic. In clinical practice it is used for induction and maintenance of anesthesia, procedural sedation, acute pain management, and — under controlled, supervised protocols — as a treatment for certain psychiatric conditions.

How it works (brief)

Ketamine is an N-methyl-D-aspartate (NMDA) receptor antagonist. By modulating glutamate signaling and related neural pathways, it produces dissociative anesthesia at higher doses and rapid changes in mood and perception at lower, controlled doses. Its mechanisms in psychiatric treatment are an area of active research.

Clinical uses

• Anesthesia & Procedural Sedation: Rapid-acting anesthetic for induction and short procedures, often used when maintaining airway reflexes is desirable.
• Acute Pain & Analgesia: Used in emergency and perioperative settings for severe pain or as an adjunct to opioid-sparing strategies.
• Treatment-Resistant Depression (TRD): Certain formulations (including intranasal esketamine) are approved in some countries for adults with TRD when given under clinical supervision. Intravenous ketamine infusions are used off-label in specialized clinics under strict protocols.
• Other Psychiatric Uses (research): Ongoing studies examine ketamine for bipolar depression, PTSD, and suicidality in controlled settings.

How it’s administered in medical settings

Ketamine delivery varies with indication and must be supervised by qualified clinicians. Common routes include intravenous (IV), intramuscular (IM), and intranasal (esketamine). Dosing, monitoring, and post-treatment observation are essential components of safe administration.

Benefits & safety considerations

Potential benefits: rapid onset of anesthesia and, in some cases, fast antidepressant effects when used in specialist settings.

Common side effects: dissociation, dizziness, nausea, elevated heart rate and blood pressure, perceptual changes, and transient cognitive effects.

Risks & contraindications: potential for abuse, cognitive or bladder toxicity with chronic nonmedical use, cardiovascular stimulation (caution in unstable heart disease), and psychotomimetic effects in susceptible individuals. Not appropriate for unsupervised use.

Legal & regulatory notes

Ketamine is a controlled medication in many jurisdictions and is legally available only through licensed medical providers or approved products. Specific approvals (for example, intranasal esketamine for TRD) vary by country and regulatory agency.

Guidance for patients

• Discuss potential benefits, risks, and alternatives with a licensed clinician.
• Ensure treatment is provided in a reputable medical setting with appropriate monitoring.
• Report history of cardiovascular disease, psychosis, substance use disorder, or pregnancy to your provider before treatment.