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RecruitingNCT06982183Updated May 13, 2026

The Effects of Propranolol and Hydrocortisone on Military-Relevant Performance Outcomes

A Phase 4 interventional study of Propranolol and Hydrocortisone in Fear of Spiders and Acute Stress Reaction, sponsored by Walter Reed Army Institute of Research (WRAIR). Recruiting at 1 site in United States. Open to participants aged 18 Years to 40 Years. Per ClinicalTrials.gov, last updated 2026-05-13.

Sponsored by Walter Reed Army Institute of Research (WRAIR) · Phase 4, Interventional, and Prevention

From the registry’s dates

  • Started May 2025; still recruiting 1 year 5 months later.
Phase
Phase 4
Study type
Interventional
Enrollment
88
Allocation
Randomized
Ages
18 Years to 40 Years
Sex
All
01

Study summary

This clinical trial aims to evaluate the nature and duration of effects of three FDA-approved medications (propranolol and hydrocortisone) on military-relevant cognitive, emotional, and motor performance following an exposure to a stressful situation (i.e., exposure to a tarantula) in physically healthy adult volunteers (aged 18 - 40) with fear of spiders to help the future development of medications for treating Acute Stress Reactions.

The main questions this study aims to answer are:

Will placebo treatment (oral placebo) result in significant decrements in Psychomotor Vigilance Task (PVT) performance compared to propranolol treatment?

Will placebo treatment [intramuscular (IM) placebo] result in significant decrements in PVT performance compared to hydrocortisone treatment?

Participants will receive one of five study medications (oral propranolol, oral placebo, IM hydrocortisone, or IM placebo) after a brief exposure to a tarantula. Participants will complete cognitive and simple motor tasks and psychological assessments before and after the study medication administration.

02

Conditions studied

  • Fear of Spiders
  • Acute Stress Reaction

Keywords

  • Fear of Spiders
  • propranolol
  • hydrocortisone
  • randomized controlled trial
  • neuropsychological tests
  • acute stress reaction
03

In context

Arachnophobia

26 studies on the registry are indexed under Arachnophobia; 2 are open to participants now.

This study's planned enrollment of 88 is above the median of 60 across 26 interventional studies indexed under Arachnophobia.

Browse Arachnophobia studies →

Lead sponsor

Walter Reed Army Institute of Research (WRAIR) is the lead sponsor of 20 studies on the registry; 5 are open to participants now.

Counted across the registry records on this site, refreshed daily.

04

Who can participate

Ages eligible
18 Years to 40 Years
Sexes eligible
All
Accepts healthy volunteers
No

Go through the criteria one by one — yes, no or not sure — and take the list to your doctor or the study team. Kept in this browser only.

Inclusion criteria

  • Male and non-pregnant, non-lactating females 18 to 40 (inclusive) years of age.
  • Females of must be on some form of , if sexually active (e.g., oral contraceptive, condom, intrauterine device, etc.)
  • Score of 80% or greater on a "Volunteer Comprehension Assessment" test.
  • Score equal to or greater than 54 on the Fear of Spiders Questionnaire.
  • Body weight between 91 and 250 pounds (inclusive).
  • Live close enough to be able to commute to Walter Reed Army Institute of Research during the study participation.

Exclusion criteria

Exclusion Criteria:

  • due to study medications, including a history of allergic/ reactions to a beta blocker or a , or a history of other adverse reactions to these classes of drugs (such as an episode of steroid psychosis).
  • A history of allergic reactions to a spider bite.
  • A history of abuse or addiction to illicit drugs (including marijuana) or prescribed medication (e.g., opioid) (diagnosed or suspected based on the medical history).
  • Use a nicotine product (e.g., cigarette, cigar, vape) more than 3 days per week.
  • Self-reported caffeine use in excess of 600 mg (e.g., approximately 10 caffeinated sodas or approximately 29 ounces of brewed coffee) per day on average or not being able to go without caffeine during the In-Lab visits.
  • History of neurologic disorder (to include but not limited to epilepsy, hydrocephalus, MS). An infrequent or resolved single neurological event (e.g., childhood seizure, rare sporadic migraine headaches, resolved meningeal infection with no sequelae) or a history of mild traumatic brain injury may be deemed non-exclusionary at the discretion of the examining study medical investigator
  • Score of 10 or above on the Beck Depression Inventory (BDI) or a score of > 0 on item 9 "Suicidal Thoughts or Wishes" of the BDI
  • Score of 41 or above on the State-Trait Anxiety Inventory - Trait (STAI-T).
  • Score of 20 or above on the PROMIS Emotional Distress - Anxiety - Short Form.
  • Score of 33 or above on the PTSD Checklist, 5th Edition (PCL-5)
  • History of cardiovascular disease (to include but not limited to arrhythmias, valvular heart disease, congestive heart failure, history of sudden cardiac death or myocardial infarction).
  • A history of asthma or any type of reactive airways disease or any acute or chronic pulmonary disorder that could lead to a compromise of blood oxygenation in the setting of a modest reduction in tidal volume or respiratory rate, to include neuromuscular disorders.
  • Regularly work night shifts or have a habitual sleep/wake schedule that is not conducive to compliance with the recommended sleep time (11:00 pm - 6:00 am) during participation (e.g., extremely early or late habitual bedtime or rise time, to be determined on a case-by-case basis by the principal investigator or an associate investigator).
  • A diagnosis of sleep apnea.
  • Kidney disease or kidney abnormalities, liver disease or liver abnormalities, or any other metabolic derangements (endocrine disorders, hyperglycemia, etc.) that could alter neurophysiological function.
  • Liver disease or significant liver abnormalities as determined by examining study medical investigator.
  • Self-reported history of hospitalization for a psychiatric disorder within the past year or with a previous history of a psychotic, bipolar disorder or personality disorder. For a history of a diagnosis of any other psychiatric disorder, a potential participant's symptoms must either be resolved to a degree that a diagnosis is no longer applied or their symptoms must have been stabilized by pharmacological or nonpharmacological treatments for a period of at least 90 days or greater as deemed exclusionary or non-exclusionary at the discretion of the examining study medical investigator.
  • Self-reported or suspected current use of antipsychotics, anticonvulsants, or mood stabilizers, to be determined on a case-by-case basis by the examining study medical investigator.
  • Self-reported or suspected current use of products or drugs that have CNS depressant effects, to be determined on a case-by-case basis by the examining study medical investigator.
  • Self-reported or suspected use of products or drugs that cannot be safely discontinued during in-laboratory phases, to be determined on a case-by-case basis by the examining study medical investigator.
  • Self-reported or suspected current heavy alcohol use (minimum limit to define heavy alcohol use is 14 drinks per week for males and 7 drinks per week for females or as determined by the examining study medical investigator).
  • (Females only) Positive urine pregnancy result
  • (Females only) Self-reported or suspected current breast-feeding or collecting breast-milk.
  • Resting blood pressure above 140/90 or resting pulse > 110 beats per minute. Note that if a repeat measurement is within range, the volunteer will not be excluded.
  • Resting blood pressure below 100/60 or pulse oxygenation \<92%. Volunteers with a resting pulse \< 60 bpm will be excluded unless a history of regular vigorous aerobic exercise and findings on the physical examination (including ) suggest a high level of cardiovascular fitness, in which case a resting pulse in the range of 50 - 59 bpm may not be exclusionary.
  • BMI ≥ 31. The inclusion of individuals with BMI between 30 and 31 (Obese Class I) will be determined using medical investigator's discretion.
  • values (as determined by the reviewing study medical investigator) for any hematology or chemistry parameter. Reviewing study medical investigator may opt to repeat any clinically significant tests and include volunteers whose repeat test values are not clinically significant.
  • Currently on or recently ended immunotherapy (e.g., allergy shots).
  • Have taken a vaccine within 30 days prior to enrollment to the study. For volunteers who report recently taking a vaccine during the screening visit, their In-Lab Day 1 visit will be scheduled at least 30 days after the date of the most recent vaccination.
  • Positive urine drug result during screening visit or In-Lab Days 1- 2; Exhibiting behaviors consistent with illicit drug use on In-Lab Day 3.
  • Positive saliva alcohol result during screening visit or In-Lab Days 1-3.
  • Inability to read and sign consent.
  • Failure to obtain required approved official leave to participate (federal civilian employees and active duty military only)
  • Failure to cooperate with requirements of the study
  • Failure to provide viable emergency contact(s) for the duration of the study
  • Self-reported or suspected current use of illicit drugs (including but not limited to benzodiazepines, amphetamines, cocaine, marijuana).
  • Current use and/or prescription for opioid, steroid or anti-hypertensive and/or any medication the Medical Investigator deems would interact adversely with study compounds.
  • Current use of medications that can adversely interact with propranolol, hydrocortisone and/or morphine to include anti-depressants that are cytochrome P450 2D6 inhibitors.
  • Current diabetes.
  • GI disorders - motility disorders
  • Failure to pass certain tests
  • Failure to provide a social security number or tax identification number in order to be paid for screening and participation in the study.
  • Current participation in another ongoing clinical trial
Terms in these criteria, in plain language(7)

Underlined terms in the criteria open these too. Explained by clinicaltrials.gg, not part of the registry record. The study team decides who can take part.

Childbearing potential

Able to become pregnant: from the first period until menopause, unless permanently unable to through surgery (removal of the womb, or of both ovaries or both fallopian tubes).

Criteria for people of childbearing potential usually ask for a negative pregnancy test and for contraception during the study and for a time after it.

Contraception

Ways of preventing pregnancy. “Highly effective” methods fail less than 1% of the time a year when used correctly — for example an IUD or an implant.

Criteria usually say which methods count and how long to keep using them after the last dose, sometimes for male participants too. Some studies accept a partner’s vasectomy if it was confirmed successful and that person is the participant’s only sexual partner.

Contraindication

A reason a treatment, test or procedure should not be given to a particular person, such as an allergy, another illness or a medicine they take.

Hypersensitivity

An allergy, or another reaction of the immune system, to a substance. “Hypersensitivity to the study drug” means a known allergic reaction to it — not every side effect a medicine can have.

Corticosteroids (steroids)

Anti-inflammatory medicines such as prednisone, prednisolone and dexamethasone — not the anabolic steroids used for muscle.

Studies differ in what they allow: check which steroid medicines, routes (tablets, injections, creams, inhalers, eye drops) and doses this study accepts.

BMI (body mass index)

Weight in kilograms divided by height in metres squared. Example: 70 kg and 1.75 m gives 70 ÷ (1.75 × 1.75) ≈ 22.9.

What counts as overweight or obesity differs between countries (some use lower cut-offs), so go by the range the study states.

Clinically significant

Judged by the study doctor to matter for your health or for the study. It is a doctor’s decision, so ask the study team if you are unsure whether something counts.

05

Study design

Phase
Phase 4
Primary purpose
Prevention
Allocation
Randomized
Intervention model
Parallel assignment
Masking
Quadruple (Participant, Care provider, Investigator, Outcomes assessor)
Enrollment
88 participants (estimated)

Study arms

  • Active comparator
    Propranolol (oral)

    Drug: Propranolol

  • Placebo comparator
    Placebo (oral)

    Drug: Placebo (oral)

  • Active comparator
    Hydrocortisone (IM)

    Drug: Hydrocortisone

  • Placebo comparator
    Placebo (IM)

    Drug: Placebo (IM)

Interventions

  • An administration of a 40-mg propranolol capsule immediately after tarantula exposure

  • An intramuscular administration of 62.5 mg/1 ml of hydrocortisone immediately after tarantula exposure

  • DrugPlacebo (oral)

    An administration of a placebo capsule after tarantula exposure

  • DrugPlacebo (IM)

    An intramuscular administration of 1 ml of saline immediately after tarantula exposure

06

What researchers measure

Primary outcomes

  1. Psychomotor Vigilance Task

    Measure of cognitive performance. Reaction time (millisecond)

    Time frame: Baseline and post-treatment time points within approximately 7 hours following the study medication administration.

Secondary outcomes

  1. Go/No-Go task

    Measure of cognitive performance.

    Time frame: Baseline and post-treatment time points within approximately 7 hours following the study medication administration.

  2. Matching to Sample task

    Measure of cognitive performance

    Time frame: Baseline and post-treatment time points within approximately 7 hours following the study medication administration.

  3. Simple Reaction Time task

    Measure of cognitive performance.

    Time frame: Baseline and post-treatment time points within approximately 7 hours following the study medication administration.

  4. The Automated Neuropsychological Assessment Metrics (ANAM) Mood Scale

    Measure of mood.

    Time frame: Baseline and post-treatment time points within approximately 7 hours following the study medication administration.

  5. WRAIR Mood Battery

    A short battery of measures of various aspects of mood.

    Time frame: Baseline and post-treatment time points within approximately 7 hours following the study medication administration.

  6. Heart rate

    Continuous measure of heart rate.

    Time frame: Before, during, and after behavioral approach task. Approximately 1 hour.

  7. Biosway

    Measure of motor performance

    Time frame: Baseline and post-treatment time points within approximately 7 hours following the study medication administration.

  8. Triple Hop Test

    Measure of motor performance.

    Time frame: Baseline and post-treatment time points within approximately 7 hours following the study medication administration.

  9. Drug Effects Questionnaire

    Measure of subjective response to a substance.

    Time frame: Multiple time points within approximately 7 hours following the study medication administration.

  10. Subjective Fear Scale

    Subjective measure of fear. A 0 - 100 numerical scale.

    Time frame: Baseline, during the behavioral approach test, and time points within approximately 7 hours after the study medication administration.

  11. Subjective Anxiety Scale

    Subjective measure of anxiety. A 0 - 100 numerical scale.

    Time frame: Baseline, during the behavioral approach test, and time points within approximately 7 hours after the study medication administration.

  12. Subjective Stress Scale

    Subjective measure of stress. A 0 - 100 numerical scale.

    Time frame: Baseline, during the behavioral approach test, and time points within approximately 7 hours after the study medication administration.

  13. Symptom checklist

    Checklist to capture adverse drug reactions.

    Time frame: Baseline, pre-medication administration, and time points within approximately 8 hours after the medication administration.

07

Study locations

1 of 1 sites recruiting
  • Sleep Research Center (SRC), Walter Reed Army Institute of Research
    Silver Spring, Maryland 20910, United States
    Recruiting
08

Updates

Tracking since Sep 25, 2026
No changes since tracking began. The registry record was last updated on May 13, 2026, before this site started recording changes on Sep 25, 2026. Its history is on ClinicalTrials.gov ↗
09

Registry details

Key details

Study ID
NCT06982183
Lead sponsor
Walter Reed Army Institute of Research (WRAIR)
Responsible party
Sponsor
First posted
May 21, 2025
Start date
May 27, 2025
Primary completion
Sep 2026 (estimated)
Completion
Sep 2026 (estimated)
Last update
May 13, 2026

Study contacts

John Hughes, MD
Contact
john.d.hughes4.civ@health.mil
301-319-3214

Oversight

Data monitoring committee
No
FDA-regulated drug
Yes
FDA-regulated device
No
View the source record on ClinicalTrials.gov ↗

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Studies of the drugs tested here: Propranolol · Hydrocortisone

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