What is the recommended dose of ketamine (Ketamine) for agitation?

Recommended Ketamine Dosing for Agitation

For acute agitation, the recommended ketamine dose is 2 mg/kg IM or 1-1.5 mg/kg IV, with continuous monitoring of vital signs and airway status. 1, 2

Dosing by Route of Administration

Intravenous (IV) Administration

• Initial dose: 1-1.5 mg/kg IV for rapid sedation of agitated patients 1
• Onset of action: 30-96 seconds, allowing for quick intervention 1
• Recovery time: Average 84 minutes (range 22-215 minutes) 3
• Higher doses (>2.5 mg/kg IV) are associated with increased risk of adverse effects including emesis 4

Intramuscular (IM) Administration

• Initial dose: 2-4 mg/kg IM for severe agitation 1, 2
• Traditional higher doses (4-6 mg/kg IM) may carry increased risk of intubation 5
• Reduced-dose protocol (2 mg/kg IM) has shown 87% effectiveness with lower intubation rates 2
• Onset of action: Approximately 3-5 minutes 1
• Recovery time: Slightly longer than IV administration, approximately 90 minutes 3

Monitoring Requirements

• Continuous monitoring of vital signs is essential during both administration and recovery 1
• Key parameters to monitor:
  • Oxygen saturation (should remain >93% on room air) 1
  • Heart rate (expect increase of approximately 8-18%) 1, 6
  • Blood pressure (expect increase of approximately 17 mm Hg systolic) 6

Potential Adverse Effects

• Respiratory:

  • Transient hypoxia: 1.8% of cases 5
  • Laryngospasm: 1.3% of cases 5
  • Higher intubation rates when used by ground EMS (30.5%) compared to ED administration (1.8%) 5

• Gastrointestinal:

  • Emesis: 5.2-8.4% of cases, with higher risk in early adolescents and with IM administration 4, 5

• Neurological:

  • Mild recovery agitation: 7.6% of cases 4
  • Clinically significant agitation: 1.4-3.5% of cases 4, 5

Important Clinical Considerations

• 62.5% of patients may require additional medication for continued agitation after initial ketamine dose 6
• Ketamine is often effective as a second-line agent when other sedatives have failed 2
• Risk factors for increased adverse events:
  • Unusually high IV doses (initial >2.5 mg/kg or total >5.0 mg/kg) 4
  • Low IM doses (<3.0 mg/kg) may be associated with inadequate sedation 4
  • Increasing age (peak emesis risk at 12 years) 4

Special Populations

• Alcohol or drug intoxication:

  • Present in 40.6% of patients receiving ketamine for agitation in one study 6
  • No significant increase in adverse effects even with 21.9% alcohol intoxication 6
  • Use caution and consider dose reduction in intoxicated patients 1

• Contraindications:

  • Use should be avoided in patients with ischemic heart disease, cerebrovascular disease, or uncontrolled hypertension 1