The Effects of Low Dose Ketamine on Cardiovascular Function


Low dose ketamine is used for pain management and for the treatment of anxiety and depression. Prior studies on low dose ketamine have noted short-term (minutes to hours) increases or decreases in blood pressure. Blood pressure that is too high or too low can be problematic if untreated. It is unknown exactly how low dose ketamine affects blood pressure. In fact, no prior studies have measured sympathetic nervous system activity after low dose ketamine has been given to an adult. Because sympathetic nervous system activity has a large influence on blood pressure, we need to know how exactly low dose ketamine affects these body systems. Therefore, in this research we will study how low dose ketamine affects sympathetic nervous system activity and cardiovascular function. The results from this research will inform doctors about how low dose ketamine affects the sympathetic nervous system, heart, and blood vessels.

Study Type

  • Study Type: Interventional
  • Study Design
    • Allocation: Randomized
    • Intervention Model: Crossover Assignment
    • Primary Purpose: Basic Science
    • Masking: Triple (Participant, Investigator, Outcomes Assessor)
  • Study Primary Completion Date: March 31, 2023


  • Drug: Ketamine
    • Low dose ketamine – Ketalar (Racemic Ketamine Hydrochloride) Saline – Isotonic/Normal Saline
  • Drug: Saline (placebo)
    • Saline (placebo)

Arms, Groups and Cohorts

  • Experimental: Low Dose Ketamine
  • Placebo Comparator: Saline (placebo)

Clinical Trial Outcome Measures

Primary Measures

  • Muscle Sympathetic Nerve Activity Burst Frequency
    • Time Frame: This outcome will be assessed within one trial lasting up to approximately five hours
    • We will measure muscle sympathetic nerve activity (MSNA), quantified as burst frequency and/or incidence, using microneurography

Secondary Measures

  • Arterial Blood Pressure
    • Time Frame: This outcome will be assessed within one trial lasting up to approximately five hours
    • We will measure arterial blood pressure, quantified as systolic, mean, and/or diastolic pressure, using an automated monitor before and after administration of low dose ketamine.

Participating in This Clinical Trial

Inclusion Criteria

  • Non-obese (body mass index less than 30 kg/m2)

*alternatively, individuals will be permitted to participate if they have a body mass index value below 35 kg/m2 but a waist circumference below 88 cm for females and 102 cm for males

  • Systolic blood pressure <140 mmHg
  • Diastolic blood pressure <90 mmHg

Exclusion Criteria

  • Participants who have cardiac, respiratory, neurological, and/or metabolic illnesses
  • Current or previous use of anti-hypertensive medications
  • Any known history of renal or hepatic insufficiency/disease
  • Pregnancy or breast feeding
  • Current smokers, as well as individuals who regularly smoked within the past 3 years
  • Individuals with a history of drug abuse
  • Individuals who have an unexplained positive urine drug screen (e.g., some agents cause false-positive results, but when the agent is abstained for hours/days/weeks, the repeated drug screen is negative. One example could be an over-the-counter supplement)

Gender Eligibility: All

Minimum Age: 18 Years

Maximum Age: 45 Years

Are Healthy Volunteers Accepted: Accepts Healthy Volunteers

Investigator Details

  • Lead Sponsor
    • University of Texas Southwestern Medical Center
  • Provider of Information About this Clinical Study
    • Principal Investigator: Craig Crandall, Professor – University of Texas Southwestern Medical Center
  • Overall Contact(s)
    • Ileana Hill, BSN, 2143456502,

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