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Study on the Effect of Fentanyl and Naloxone on Breathing Patterns in Healthy Individuals

Fast replyRegistered drugNo placebo
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What is this trial about?

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

This clinical trial is focused on understanding how the medication fentanyl affects breathing patterns in healthy individuals. Fentanyl is a powerful medication often used to manage pain, and this study aims to explore its effects on breathing when administered to volunteers. The study will also involve the use of naloxone, a medication known for reversing the effects of opioids like fentanyl.

The purpose of the study is to observe changes in breathing during and after the administration of fentanyl. Participants will receive the medication through an injection, and their breathing patterns will be closely monitored. The study will look at various aspects of breathing, such as the rate of breaths per minute and oxygen levels in the blood, to understand how fentanyl influences these factors.

Throughout the study, participants will be observed for any changes in their breathing, including any significant drops in breathing rate or oxygen levels. The study will help researchers gain insights into the effects of fentanyl on breathing, which could be important for its use in medical settings. The trial is expected to run for a specific period, during which participants will be monitored to ensure their safety and gather necessary data.

The research process

The trial runs in 5 steps – from screening to follow-up. Each step says what happens and what the team monitors.

  1. Step 1

    Joining the study

    Upon joining the study, you will be informed about the purpose and procedures involved. The study aims to explore how the medication fentanyl affects breathing patterns.

    You will be required to confirm your age, which should be between 18 and 45 years, and your body mass index (BMI), which should be between 19 and 30 kg/m².

  2. Step 2

    Initial assessment

    An initial assessment will be conducted to ensure you meet the study's health criteria. This includes confirming that you are a healthy individual with no underlying medical conditions.

  3. Step 3

    Medication administration

    You will receive an injection of fentanyl citrate, which is a medication used to study its effects on breathing. The dosage will be 50 micrograms per milliliter, administered intravenously.

    Additionally, naloxone hydrochloride may be administered as a solution for injection or infusion at a dosage of 400 micrograms per milliliter, also intravenously.

  4. Step 4

    Monitoring phase

    During the study, your breathing patterns will be closely monitored. This includes measuring your respiratory rate, oxygen levels, and carbon dioxide levels in your blood.

    The primary focus will be on the levels of carbon dioxide in your blood during the recovery phase, which is the last 90 minutes of the study.

  5. Step 5

    Recovery phase

    In the recovery phase, your breathing will continue to be monitored to observe any changes after the administration of the medication.

    The study will look for specific respiratory events, such as a low breathing rate, low oxygen saturation, or changes in carbon dioxide levels.

Who can join the trial?

4 criteria

  • Must be a healthy individual with no medical conditions.
  • Age must be between 18 and 45 years.
  • Body mass index (BMI) must be between 19 and 30 kg/m2. BMI is a measure of body fat based on height and weight.
  • Both males and females can participate.

Who cannot join the trial?

4 criteria

  • Participants must be healthy with no medical conditions.
  • Participants must be within the specified age range.
  • Both male and female participants are eligible.
  • Participants must not belong to any vulnerable population groups.
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Investigated drugs

Fentanyl is a strong pain-relieving medication often used in medical settings to help manage severe pain. In this study, it is being used to see how it affects breathing patterns in healthy men and women. The researchers want to understand how people's breathing changes when they receive fentanyl, both during and after its administration. This information can help doctors better understand how fentanyl affects the body, especially in terms of breathing, which is important for ensuring patient safety during its use.

What is already known about the treatment

Fentanyl – Fentanyl is administered as an injection or a patch applied to the skin, and it is currently being studied for its effects on breathing patterns in healthy individuals under simulated post-surgical conditions. In medical literature, fentanyl is well-known as a powerful pain reliever often used in hospitals for managing severe pain. Its main therapeutic use is to provide pain relief, especially after surgery or for chronic pain conditions. At the molecular level, fentanyl works by binding to specific receptors in the brain called opioid receptors, which helps to block the sensation of pain. It is classified pharmacologically as an opioid analgesic.

Investigated diseases

None, healthy subjects – This refers to individuals who do not have any diagnosed medical conditions or diseases. They are considered to be in a state of overall physical and mental well-being. In clinical studies, healthy subjects are often used as a control group to compare against individuals with specific conditions. Their bodily functions, such as respiratory and cardiovascular systems, are typically within normal ranges. These individuals do not exhibit symptoms or signs of illness. They are often selected for studies to understand normal physiological responses.
Trial detailsLast updated 2 Oct 2026
Age18+ yearsPhasePhase IIITrial ID2023-508915-22-00Estimated enrolment12 patientsSponsorLeids Universitair Medisch Centrum (LUMC)

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