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Enrolling by Invitation

NCT Number: NCT05477004

Observational Study of Ketamine Infusions for the Treatment of Chronic Pain

This observational study will collect prospectively specified data on patient characteristics and clinically relevant outcomes in patients who receive a ketamine infusion at Stanford Pain Management Center for the treatment of chronic pain, with the goal of identifying treatment responders and relationships between patient characteristics and treatment response.

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Key information

Conditions

Chronic Pain Autonomic Nervous System Diseases Complex Regional Pain Syndromes Mental Disorders Nervous System Diseases Neuralgia Neurologic Manifestations Neuromuscular Diseases Pain Pain, Intractable Pathological Conditions, Signs and Symptoms Peripheral Nervous System Diseases Signs and Symptoms Somatoform Disorders

Age range

18 year and older

Sex eligibility

All sexes

Study type

Observational

Primary location

Stanford University

Stanford, California, 94305, United States

About this study

Ketamine is a type of anesthetic drug which has been used off-label to treat chronic pain. The effectiveness of intravenous ketamine and its duration of effect are not well-understood. There is high variability in response to ketamine, and it remains unclear which patient characteristics are associated with favorable outcomes. This observational study will collect a wide range of patient-reported outcomes via digital surveys: once at baseline before treatment, and up to 7 follow-up surveys for up to 12 months following a single ketamine infusion. Survey data will be supplemented by clinical data obtained from electronic medical records.

Who can participate

Healthy volunteers accepted: No

Only the study team can determine whether someone qualifies for participation.

Inclusion criteria

  • Has been seen at Stanford's Pain Management Center for a doctor's visit at least once.
  • Is scheduled to undergo at least 1 ketamine infusion for the treatment of any chronic pain condition.
  • Have a valid email address and consents to receiving surveys by email.
  • Able to read, understand, and respond to English-language surveys on an electronic device such as a cell phone, tablet, or computer.
  • Able to read, understand, and provide written, dated informed consent.

Exclusion criteria

  • Has their ketamine infusion cancelled, which may occur before or after consenting to this study.

Treatment and study plan

ketamine

Drug

A multi-day continuous ketamine infusion delivered intravenously at subanesthetic doses in a monitored setting

Other names: Ketalar

Primary outcomes

  1. Change from baseline Patient Global Impression of Change (PGIC) in overall status; measured with PGIC Scale

    Time frame: 1 week, 2 weeks, 1 month, 2 months, 3 months, 6 months, 12 months (or up to the time of their next ketamine infusion)

    The PGIC Scale is a single-question 7-point Likert scale ranging from "Very much improved" to "Very much worse."

Secondary outcomes

  1. Change from baseline average pain intensity; measured with Numeric Rating Scale (NRS)

    Time frame: 1 week, 2 weeks, 1 month, 2 months, 3 months, 6 months, 12 months (or up to the time of their next ketamine infusion)

    Participants rate their average pain intensity over the last 7 days using whole numbers on a 0-to-10 scale, with higher values indicative of more pain.

Other outcomes

  1. Change from baseline opioid use; measured with 2 questions

    Time frame: 1 week, 2 weeks, 1 month, 2 months, 3 months, 6 months, 12 months (or up to the time of their next ketamine infusion)

    Question 1: Participants are asked whether they have used any opioid medications since their last ketamine infusion (yes/no). Question 2: Participants are asked to rate how their opioid use has changed on a 4-point scale ranging from "I have not used any opioids since my last ketamine infusion" to "I am using more opioids after my last ketamine infusion."

  2. Change from baseline pain catastrophizing score; measured with Pain Catastrophizing Scale - Short Form

    Time frame: 1 week, 2 weeks, 1 month, 2 months, 3 months, 6 months, 12 months (or up to the time of their next ketamine infusion)

    Pain Catastrophizing Scale - Short Form is a 4-item scale with a total score ranging from 0-16, with higher scores indicative of more catastrophizing.

  3. Change from baseline pain interference score; measured with PROMIS Pain Interference

    Time frame: 1 week, 2 weeks, 1 month, 2 months, 3 months, 6 months, 12 months (or up to the time of their next ketamine infusion)

    PROMIS Pain Interference is a computerized adaptive test with results reported as a T-score (mean score of 50 and standard deviation of 10), with higher T-scores indicative of more pain interference.

  4. Change from baseline physical function score; measured with PROMIS Physical Function

    Time frame: 1 week, 2 weeks, 1 month, 2 months, 3 months, 6 months, 12 months (or up to the time of their next ketamine infusion)

    PROMIS Physical Function is a computerized adaptive test with results reported as a T-score (mean score of 50 and standard deviation of 10), with higher T-scores indicative of better physical function.

  5. Change from baseline depression score; measured with PROMIS Depression

    Time frame: 1 week, 2 weeks, 1 month, 2 months, 3 months, 6 months, 12 months (or up to the time of their next ketamine infusion)

    PROMIS Depression is a computerized adaptive test with results reported as a T-score (mean score of 50 and standard deviation of 10), with higher T-scores indicative of more depression.

  6. Change from baseline anxiety score; measured with PROMIS Anxiety

    Time frame: 1 week, 2 weeks, 1 month, 2 months, 3 months, 6 months, 12 months (or up to the time of their next ketamine infusion)

    PROMIS Anxiety is a computerized adaptive test with results reported as a T-score (mean score of 50 and standard deviation of 10), with higher T-scores indicative of more anxiety.

  7. Change from baseline sleep disturbance score; measured with PROMIS Sleep Disturbance

    Time frame: 1 week, 2 weeks, 1 month, 2 months, 3 months, 6 months, 12 months (or up to the time of their next ketamine infusion)

    PROMIS Sleep Disturbance is a computerized adaptive test with results reported as a T-score (mean score of 50 and standard deviation of 10), with higher T-scores indicative of more sleep disturbance.

  8. Change from baseline global health score; measured with PROMIS Global Health

    Time frame: 1 week, 2 weeks, 1 month, 2 months, 3 months, 6 months, 12 months (or up to the time of their next ketamine infusion)

    PROMIS Global Health is a computerized adaptive test with results reported as a T-score (mean score of 50 and standard deviation of 10), with higher T-scores indicative of better overall physical health, mental health, social health, pain, fatigue, and overall perceived quality of life.

  9. Change from baseline body areas affected by pain; measured with CHOIR Body Map

    Time frame: 1 week, 2 weeks, 1 month, 2 months, 3 months, 6 months, 12 months (or up to the time of their next ketamine infusion)

    CHOIR Body Map is a validated self-report body map where participants select areas of the body affected by pain, with a higher number of selected areas indicative of more widespread pain.

Sponsors and collaborators

Lead sponsor

Theresa Lii

Other

Registry information

Official study title

Ketamine Infusion for the Treatment Chronic Pain in Adults: a Prospective Observational Study to Characterize Predictors and Outcomes

Important dates

Study start
2022
Primary completion
2026
Study completion
2026
First posted
Jul 27, 2022
Registry last updated
Dec 19, 2025

OpenTrials presents study information sourced from ClinicalTrials.gov. The official registry record should be consulted for the latest information.

View the official ClinicalTrials.gov record (opens in a new tab)

This listing is for discovery and informational purposes only. It is not medical advice, does not guarantee that a study is recruiting, and does not determine eligibility. Contact the study team and a qualified healthcare professional when considering participation.

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