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Propranolol hydrochloride dose-finding trial to reduce reactive aggression in patients with reactive aggression

Verified siteRegistered drugNo placebo
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What is this trial about?

A plain-language summary of the goals, design and what participants do

The study focuses on people who have Reactive aggression, which is a sudden, intense anger that can lead to aggressive actions. It evaluates an oral liquid medicine containing propranolol to find out whether different amounts of the drug can lower these aggressive reactions. The purpose of the study is to determine a dose‑dependent effect of propranolol in reducing reactive aggression.

Participants will attend several visits where they will receive either the medicine at low, medium, or high strength, or a placebo, on separate days. After each dose, they will enter a computer‑generated three‑dimensional environment called virtual reality that presents challenging situations, and they will be asked to describe how angry they feel while researchers observe their behavior. Simple checks of blood pressure and heart rate will also be taken.

At each visit, participants will complete short questionnaires about their mood and level of anger, and they will perform brief tasks that help researchers understand changes in aggression. The study team will monitor safety throughout the visits and will record any side effects that may occur.

The research process

The trial runs in 6 steps – from screening to follow-up. Each step says what happens and what the team monitors.

  1. Step 1

    Enrollment and consent

    After you join the study you sign an informed consent form that explains the purpose and procedures.

    You provide personal information, medical history, and details about any current medications.

    A brief health check is performed to confirm eligibility.

  2. Step 2

    Baseline assessments

    You complete the Social Dysfunction and Aggression Scale (SDAS‑9), a questionnaire that rates aggressive behavior in everyday situations.

    You also complete the Spielberger Anger Expression Scale (AEX), which measures how angry you feel at that moment.

    Your mood is evaluated with the Profile of Moods State (POMS‑SF) questionnaire, which asks about feelings such as tension, vigor, and depression.

    A series of neuropsychological tests are administered to assess attention, reaction time, and other cognitive functions.

    Your blood pressure and heart rate are measured to provide baseline vital‑sign values.

  3. Step 3

    Medication start

    You receive HEMANGIOL oral solution, which contains the active ingredient propranolol hydrochloride.

    Each dose contains 320 mg of propranolol; the solution concentration is 3.75 mg per milliliter, so the exact volume is measured by study staff.

    The medication is taken by mouth according to the schedule provided for each testing period.

    The same schedule is followed when a non‑active placebo is administered, allowing comparison between active drug and placebo.

  4. Step 4

    Virtual reality testing sessions

    You wear a headset that presents computer‑generated, mildly provocative scenarios designed to elicit a reaction.

    During each scenario you receive either a dose of propranolol or a placebo in a random order.

    Researchers observe your behavior for signs of aggression, and after each scenario you complete the anger scale again.

    Your blood pressure and heart rate are recorded during the session to track physiological responses.

  5. Step 5

    Repeated assessments after each dosing period

    Following each virtual reality session you repeat the aggression scale, anger scale, and mood questionnaire to capture any changes.

    Vital signs, including blood pressure and heart rate, are measured again.

    The neuropsychological assessment battery may be repeated to compare performance under the different conditions.

  6. Step 6

    Final visit and study completion

    After the last testing session you complete any remaining questionnaires and undergo a final health check.

    Any unused medication is returned to the study staff.

    The study is formally closed for you, and no further study procedures are required.

Who can join the trial?

5 criteria

  • Male – you must be a man.
  • Age 18 or older – you must be at least 18 years old.
  • Normal vision or corrected normal vision – you must see well, either naturally or with glasses or contact lenses.
  • Ability to give informed consent – you must be able to understand the study information and agree to take part voluntarily.
  • Willingness to follow study procedures – you must be ready to do the required tasks, such as taking the medication and attending study visits.

Who cannot join the trial?

16 criteria

  • Significant kidney or liver disease – serious problems with these organs that affect how they work.
  • Use of any medication or psychoactive substance within the past 4 weeks – taking any drug, including those that affect the brain, in the month before the study, especially those listed in the study protocol.
  • Symptoms of a psychotic disorder or major mood disorder (such as bipolar disorder) – experiencing signs of conditions like schizophrenia (psychotic disorder) or severe mood swings (bipolar disorder).
  • Participation in another investigational drug trial – being in a different experimental drug study now or having been in one within the last 3 months.
  • Previous motion sickness in virtual reality (VR) – having felt sick when using VR before.
  • High risk of not following study rules – the investigator believes the person may not reliably follow the study instructions.
  • Diagnosis of epilepsy – having a condition that causes recurrent seizures.
  • Currently receiving treatment for aggressive behavior – already taking medication or therapy aimed at reducing aggression.
  • Unstable medical condition – having a health problem that is not well‑controlled or could change quickly.
  • History of brain surgery for tumors or bleeding, or planned brain surgery during the study – having had or planning to have an operation on the brain.
  • Orthostatic hypotension – a significant drop in blood pressure when standing up, measured as at least a 20 mm Hg drop in systolic or a 10 mm Hg drop in diastolic pressure.
  • Heart problems such as sick sinus syndrome, second‑ or third‑degree atrioventricular block, untreated heart failure, severe peripheral artery disease, or untreated pheochromocytoma – serious conditions that affect the heart’s rhythm, blood flow, or hormone‑producing tumors.
  • History of asthma or obstructive lung disease – having breathing conditions that make it hard to get enough air.
  • Uncontrolled diabetes or thyroid disorder – blood‑sugar or thyroid hormone levels that are not kept within a safe range.
  • History of glaucoma or increased risk of glaucoma – an eye condition that can damage the optic nerve and affect vision.
  • Use of any medication within the past 4 weeks that affects liver enzymes (CYP1A2, CYP3A4, CYP2C19, CYP2D6) – taking drugs that change how the liver processes other medicines.
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Investigated drugs

Propranolol is being tested as a liquid medicine that you drink. In this study, participants take the oral solution to see if different amounts of the drug can lower sudden, intense anger or aggressive reactions. The goal is to find out how the amount taken affects its ability to calm aggressive behavior.

What is already known about the treatment

Propranolol - The medication is supplied as an oral solution (3.75 mg/mL) that is taken by mouth, usually measured with a small syringe or cup. It is a well‑known drug that is widely described in medical literature and is approved for use as a non‑selective beta‑adrenergic blocker to treat high blood pressure, chest pain, irregular heartbeats and anxiety. In this trial it is being studied to see if it can lower reactive aggression, a behavior problem. It works by blocking beta receptors, which reduces the effects of adrenaline and helps calm the heart and nervous system.

Investigated diseases

Reactive aggression - Reactive aggression is an intense, impulsive response to perceived threat or frustration. It often appears as a sudden outburst of anger or hostility that is disproportionate to the situation. Over time, individuals may experience more frequent or stronger reactions as stress accumulates. The behavior can spread to other areas of life, influencing relationships and social interactions. Repeated episodes may reinforce a pattern of quick, emotional retaliation.
Trial detailsLast updated 7 Oct 2026
Age18+ yearsPhasePhase IITrial ID2026-526545-95-00Estimated enrolment30 patientsSponsorStichting Radboud universitair medisch centrum

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