Maximum Ketamine Dosage for PTSD Treatment
The maximum recommended dose of ketamine for PTSD treatment is 0.5 mg/kg administered intravenously, which has been established as the standard therapeutic dose in clinical trials showing efficacy for PTSD symptom reduction. 1, 2
Dosing Guidelines for Ketamine in PTSD
Standard Dosing Protocol
- Initial dose: 0.5 mg/kg administered intravenously over 40 minutes
- Administration frequency: Typically twice weekly for 2-4 weeks
- Total course: 6 infusions has been shown to be effective in randomized controlled trials
Evidence Base
The most recent and highest quality evidence comes from a 2021 randomized controlled trial that demonstrated significant efficacy of repeated ketamine infusions at 0.5 mg/kg for chronic PTSD 1. This study showed:
- 67% of participants receiving ketamine at this dose were treatment responders
- The median time to loss of response was 27.5 days following completion of the 2-week course
- This dosing regimen was well-tolerated without serious adverse events
Alternative Dosing Considerations
- Lower doses (0.2 mg/kg) have been studied but with less robust evidence for efficacy 3
- A 2023 meta-analysis found that ketamine showed only a small advantage over control conditions at reducing PTSD symptoms, suggesting that optimal dosing remains an area of ongoing research 4
Safety Considerations
Monitoring Requirements
- Blood pressure and heart rate monitoring during infusion
- Assessment for dissociative symptoms
- Evaluation for emergence reactions
Contraindications
- Uncontrolled hypertension
- History of psychosis
- Severe cardiovascular disease
- Increased intracranial pressure
Clinical Application Algorithm
- Patient selection: Confirm PTSD diagnosis and ensure no contraindications
- Initial infusion: Administer 0.5 mg/kg IV over 40 minutes
- Assessment: Evaluate response 24 hours post-infusion
- Continuation: If beneficial, continue with twice-weekly infusions for 2-4 weeks (total of 6 infusions)
- Maintenance: Consider maintenance infusions based on duration of response
Important Caveats
- Ketamine for PTSD remains an off-label use
- The 2024 meta-analysis suggests potential bias in smaller studies showing larger effects 4
- Response may differ between civilian and military/veteran populations, with one study showing less robust effects in veterans 5
- Long-term safety and efficacy beyond the acute treatment phase have not been well-established
While some studies have explored other routes of administration or dosing regimens, the 0.5 mg/kg IV dose has the strongest evidence base and should be considered the maximum standard dose for PTSD treatment based on current research.