Ketanest S (Esketamine)

Esketamine is an NMDA receptor antagonist used in anesthesia and analgesia pathways.

• Induction of anesthesia: produces rapid, controllable loss of consciousness for surgical procedures.
• Analgesia: provides potent pain relief during and after operative interventions.
• Procedural sedation: offers quick onset sedation for short, minimally invasive procedures.

• Esketamine binds to and blocks the N‑methyl‑D‑aspartate (NMDA) receptor channel, reducing excitatory neurotransmission. This antagonism disrupts the perception of pain and induces a dissociative state, leading to anesthesia and analgesia. The drug also modulates opioid receptors and catecholamine release, contributing to its hemodynamic effects during administration.

Esketamine may cause a range of adverse reactions that vary in frequency and severity.

Common Side Effects

• Dizziness: transient feeling of light‑headedness.
• Nausea: mild to moderate upset stomach.
• Increased blood pressure: temporary elevation during induction.
• Vivid dreams or hallucinations: sensory disturbances during recovery.
• Dissociation: sense of detachment from environment.
• Headache: mild to moderate pain.

Serious or Rare Side Effects

• Respiratory depression: reduced breathing effort requiring support.
• Severe hypertension: marked rise in blood pressure needing intervention.
• Emergence delirium: confusion or agitation upon waking.
• Seizures: rare convulsive episodes.
• Cardiac arrhythmias: irregular heart rhythms.
• Allergic reactions: rash, itching, or anaphylaxis.

When using Ketanest S, clinicians should observe specific safety measures.

• Patient assessment: evaluate cardiovascular and neurological status before administration.
• Cardiovascular monitoring: continuously monitor blood pressure and heart rate.
• Respiratory monitoring: ensure adequate ventilation and oxygenation throughout the procedure.
• Contraindications: avoid in patients with elevated intracranial pressure or severe hepatic impairment.
• Drug interaction vigilance: review concomitant medications that may potentiate CNS effects.
• Use in elderly: start with lower doses and monitor closely for hemodynamic changes.
• Store at 2-8°C: keep refrigerated, protect from light, do not freeze or shake.

Esketamine can interact with several drug classes, requiring careful management.

Major Interactions (Avoid)

• Monoamine oxidase inhibitors (MAOIs): risk of hypertensive crisis.
• Sympathomimetic agents: may cause excessive hypertension.
• CNS depressants (e.g., benzodiazepines): can deepen sedation beyond intended levels.
• Drugs increasing intracranial pressure: may exacerbate cerebral edema.

Moderate Interactions (Monitor Closely)

• Opioids: additive analgesic effect may increase respiratory depression risk.
• Other anesthetic agents: may require dose adjustments to avoid over‑sedation.
• Antihypertensives: monitor blood pressure for potential instability.
• Anticholinergic drugs: may influence heart rate variability.