Effect of Melatonin on Sleep Patterns of Resident Trainees During Night Float Shift

April 27, 2026 updated by: Lauren Dunn, MD, University of Virginia

Anesthesiology residency requires extended and overnight shifts, which may negatively impact the quantity and quality of sleep.

Previous studies have investigated the effect of night float shift work on anesthesiology resident sleep and performance and demonstrated that total sleep quantity and time spent in deep and rapid eye movement (REM) sleep were significantly reduced during night float and did not return to baseline after 3 nights of recovery.

Melatonin is a hormone produced by the pineal gland, which regulates the circadian rhythm that governs sleep. Exogenous melatonin may be used as a sleep aid and is available over the counter in the United States. Melatonin is effective in realigning the circadian rhythm disorder caused by night shift work and increasing sleep duration; however, melatonin's effect on improving sleep in resident trainees has not been investigated. The investigators propose a prospective double-blinded randomized control trial to investigate the effect of melatonin on sleep quantity and quality in resident physicians assigned to a night float system.

Study Overview

Status

Status

Indicates the current recruitment status or the expanded access status.
Recruiting

Conditions

Conditions

The disease, disorder, syndrome, illness, or injury that is being studied. On ClinicalTrials.gov, conditions may also include other health-related issues, such as lifespan, quality of life, and health risks.

Intervention / Treatment

Intervention / Treatment

A process or action that is the focus of a clinical study. Interventions include drugs, medical devices, procedures, vaccines, and other products that are either investigational or already available. Interventions can also include noninvasive approaches, such as education or modifying diet and exercise.

Detailed Description

Residents in Post-Graduate Years 1-7 enrolled in residency programs with a night float system (anesthesiology, general surgery, obstetrics and gynecology, general medicine, and pediatrics) will be invited to participate in the study. A clinical study coordinator will assist in obtaining informed consent. After informed consent is obtained, participants will be randomized to receive either 3 mg melatonin or a matching placebo control. Medications will be prepared and randomization performed by the University of Virginia Pharmacy. Both participants and study coordinators will be blinded to the treatment group. Participants will be provided with a 12-day supply of medication at the start of the night float week. They will be instructed to take one capsule at least 20 minutes prior to going to bed at night or during the day after completing their night float shift. Subjects will be given a portable electroencephalography (EEG) monitor (ZMachine© Insight+ monitor (General Sleep Corporation, Euclid, OH))12 and will be shown how to apply the machine, monitor its functionality, and troubleshoot minor issues. They will be asked to wear the device for 2-3 nights of baseline sleep, 5-6 days of sleep during night float, and 3-4 nights of recovery following night float, for a total of 12 consecutive days. Baseline sleep data will serve as a control for each subject. EEG data collected will include: Light Sleep, Deep Sleep, REM, Arousals, Total Sleep Time, Sleep Efficiency, Latency to Persistent Sleep, Wake After Sleep Onset, Total Deep Sleep, Total REM Sleep, and Time Out of Bed. Data from two different night float periods separated by at least 2 weeks will be collected (one-week melatonin and one-week placebo in random order). Residents will also be asked to complete a daily questionnaire assessing daytime sleepiness (Epworth Sleepiness Scale) and the use of caffeine or other stimulants.

Study Type

Study Type

Describes the nature of a clinical study. Study types include interventional studies (also called clinical trials), observational studies (including patient registries), and expanded access.
Interventional

Enrollment (Estimated)

Enrollment

The number of participants in a clinical study. The "anticipated" enrollment is the target number of participants that the researchers need for the study.
50

Phase

Phase

The stage of a clinical trial studying a drug or biological product, based on definitions developed by the U.S. Food and Drug Administration (FDA). The phase is based on the study's objective, the number of participants, and other characteristics. There are five phases: Early Phase 1 (formerly listed as Phase 0), Phase 1, Phase 2, Phase 3, and Phase 4. Not Applicable is used to describe trials without FDA-defined phases, including trials of devices or behavioral interventions.
  • Early Phase 1

Contacts and Locations

This section provides the contact details for those conducting the study, and information on where this study is being conducted.

Study Contact

Study Contact

The name and contact information for the person who can answer enrollment questions for a clinical study. Each location where the study is being conducted may also have a specific contact, who may be better able to answer those questions.

Study Contact Backup

Study Locations

  • United States
    • Virginia
      • Charlottesville, Virginia, United States, 22908-0710
        • Recruiting
        • University of Virginia
        • Contact:

Participation Criteria

Researchers look for people who fit a certain description, called eligibility criteria. Some examples of these criteria are a person's general health condition or prior treatments.

Eligibility Criteria

Eligibility Criteria

The key requirements that people who want to participate in a clinical study must meet or the characteristics they must have. Eligibility criteria consist of both inclusion criteria (which are required for a person to participate in the study) and exclusion criteria (which prevent a person from participating). Types of eligibility criteria include whether a study accepts healthy volunteers, has age or age group requirements, or is limited by sex.

Ages Eligible for Study

18 years and older (Adult, Older Adult)

Accepts Healthy Volunteers

Yes

Description

Inclusion Criteria:

  • Post-Graduate Year 1-5
  • Current enrollment in anesthesiology, general surgery, obstetrics and gynecology, general medicine, or pediatrics residency at the Unversity of Virginia

Exclusion Criteria:

  • Current use of sleep aids
  • Diagnosed sleep disorder
  • History of a pacemaker or other medical device.
  • pregnant or breast-feeding females
  • Bleeding disorders
  • Depression
  • High blood pressure
  • Seizure disorders
  • History of transplant on immunosuppression therapy.

Study Plan

This section provides details of the study plan, including how the study is designed and what the study is measuring.

How is the study designed?

Design Details

  • Primary Purpose: Treatment
  • Allocation: Randomized
  • Interventional Model: Parallel Assignment
  • Masking: None (Open Label)

Arms and Interventions

Participant Group / Arm

Participant Group / Arm

A group or subgroup of participants in a clinical trial that receives a specific intervention/treatment, or no intervention, according to the trial's protocol.
Intervention / Treatment

Intervention / Treatment

A process or action that is the focus of a clinical study. Interventions include drugs, medical devices, procedures, vaccines, and other products that are either investigational or already available. Interventions can also include noninvasive approaches, such as education or modifying diet and exercise.
Experimental: Melatonin group
These subjects will receive melatonin
Dietary supplement: Melatonin
Melatonin
Placebo Comparator: Placebo group
These subjects will receive placebo
Other: Placebo
Placebo control

What is the study measuring?

Primary Outcome Measures

Primary Outcome Measures

In a clinical study's protocol, the planned outcome measure that is the most important for evaluating the effect of an intervention/treatment. Most clinical studies have one primary outcome measure, but some have more than one.
Outcome Measure
Measure Description
Time Frame
Total Sleep Time (TST)
Time Frame: 2 weeks
Measured in hours and fraction of hours, with a portable electroencephalography monitor ZMachine© Insight+ monitor (General Sleep Corporation, Euclid, OH)
2 weeks

Secondary Outcome Measures

Secondary Outcome Measures

In a clinical study's protocol, a planned outcome measure that is not as important as the primary outcome measure for evaluating the effect of an intervention but is still of interest. Most clinical studies have more than one secondary outcome measure.
Outcome Measure
Measure Description
Time Frame
Light Sleep
Time Frame: 2 weeks
Measured in hours and fraction of hours, with a portable electroencephalography monitor ZMachine© Insight+ monitor (General Sleep Corporation, Euclid, OH)
2 weeks
Deep Sleep
Time Frame: 2 weeks
Measured in hours and fraction of hours, with a portable electroencephalography monitor ZMachine© Insight+ monitor (General Sleep Corporation, Euclid, OH)
2 weeks
Rapid Eye Movement Sleep
Time Frame: 2 weeks
Measured in hours and fraction of hours, with a portable electroencephalography monitor ZMachine© Insight+ monitor (General Sleep Corporation, Euclid, OH)
2 weeks
Latency to Persistent Sleep (LPS)
Time Frame: 2 weeks
Measured in hours and fraction of hours, with a portable electroencephalography monitor ZMachine© Insight+ monitor (General Sleep Corporation, Euclid, OH)
2 weeks
Wake after Sleep Onset (WASO)
Time Frame: 2 weeks
Measured in hours and fraction of hours, with a portable electroencephalography monitor ZMachine© Insight+ monitor (General Sleep Corporation, Euclid, OH)
2 weeks
Sleep Efficiency (SE)
Time Frame: 2 weeks
monitor ZMachine© Insight+ monitor (General Sleep Corporation, Euclid, OH)
2 weeks

Other Outcome Measures

Other Outcome Measures

For clinical trials, a planned measurement described in the protocol that is used to determine the effect of an intervention/treatment on participants. For observational studies, a measurement or observation that is used to describe patterns of diseases or traits, or associations with exposures, risk factors, or treatment. Types of outcome measures include primary outcome measure and secondary outcome measure.
Outcome Measure
Measure Description
Time Frame
Epworth Sleepiness Scale
Time Frame: 2 weeks

Score 0-24 (Interpretation:

0-7: Unlikely to be abnormally sleepy. 8-9: Average amount of daytime sleepiness.

10-15: May be excessively sleepy depending on the situation. Consider seeking medical attention.

16-24: Excessively sleepy, consider seeking medical attention.)
2 weeks

Collaborators and Investigators

This is where you will find people and organizations involved with this study.

Sponsor

Sponsor

The organization or person who initiates the study and who has authority and control over the study.
University of Virginia

Investigators

Investigators

A researcher involved in a clinical study. Related terms include site principal investigator, site sub-investigator, study chair, study director, and study principal investigator.
  • Principal Investigator: Lauren Dunn, MD PHD, University of Virginia

Study record dates

These dates track the progress of study record and summary results submissions to ClinicalTrials.gov. Study records and reported results are reviewed by the National Library of Medicine (NLM) to make sure they meet specific quality control standards before being posted on the public website.

Study Major Dates

Study Start (Actual)

Study Start

The actual date on which the first participant was enrolled in a clinical study. The "anticipated" study start date is the date that the researchers think will be the study start date.
May 30, 2022

Primary Completion (Estimated)

Primary Completion

The date on which the last participant in a clinical study was examined or received an intervention to collect final data for the primary outcome measure. Whether the clinical study ended according to the protocol or was terminated does not affect this date. For clinical studies with more than one primary outcome measure with different completion dates, this term refers to the date on which data collection is completed for all the primary outcome measures. The "anticipated" primary completion date is the date that the researchers think will be the primary completion date for the study.
June 30, 2028

Study Completion (Estimated)

Study Completion

The date on which the last participant in a clinical study was examined or received an intervention/treatment to collect final data for the primary outcome measures, secondary outcome measures, and adverse events (that is, the last participant's last visit). The "anticipated" study completion date is the date that the researchers think will be the study completion date.
June 30, 2028

Study Registration Dates

First Submitted

First Submitted

The date on which the study sponsor or investigator first submitted a study record to ClinicalTrials.gov. There is typically a delay of a few days between the first submitted date and the record's availability on ClinicalTrials.gov (the first posted date).
January 6, 2023

First Submitted That Met QC Criteria

First Submitted That Met QC Criteria

The date on which the study sponsor or investigator first submits a study record that is consistent with National Library of Medicine (NLM) quality control (QC) review criteria. The sponsor or investigator may need to revise and submit a study record one or more times before NLM's QC review criteria are met. It is the responsibility of the sponsor or investigator to ensure that the study record is consistent with the NLM QC review criteria.
January 18, 2023

First Posted (Actual)

First Posted

The date on which the study record was first available on ClinicalTrials.gov after National Library of Medicine (NLM) quality control (QC) review has concluded. There is typically a delay of a few days between the date the study sponsor or investigator submitted the study record and the first posted date.
January 27, 2023

Study Record Updates

Last Update Posted (Actual)

Last Update Posted

The most recent date on which changes to a study record were made available on ClinicalTrials.gov. There may be a delay between when the changes were submitted to ClinicalTrials.gov by the study's sponsor or investigator (the last update submitted date) and the last update posted date.
May 4, 2026

Last Update Submitted That Met QC Criteria

Last Update Submitted That Met QC Criteria

The most recent date on which the study sponsor or investigator submitted changes to a study record that are consistent with National Library of Medicine (NLM) quality control (QC) review criteria. It is the responsibility of the sponsor or investigator to ensure that the study record is consistent with the NLM QC review criteria.
April 27, 2026

Last Verified

Last Verified

The most recent date on which the study sponsor or investigator confirmed the information about a clinical study on ClinicalTrials.gov as accurate and current. If a study with a recruitment status of recruiting; not yet recruiting; or active, not recruiting has not been confirmed within the past 2 years, the study's recruitment status is shown as unknown.
April 1, 2026

More Information

Terms related to this study

Additional Relevant MeSH Terms

Other Study ID Numbers

Other Study ID Numbers

Identifiers or ID numbers other than the NCT number that are assigned to a clinical study by the study's sponsor, funders, or others. These numbers may include unique identifiers from other trial registries and National Institutes of Health grant numbers.
  • HSR210118

Plan for Individual participant data (IPD)

Plan to Share Individual Participant Data (IPD)?

NO

Drug and device information, study documents

Studies a U.S. FDA-regulated drug product

No

Studies a U.S. FDA-regulated device product

No

This information was retrieved directly from the website clinicaltrials.gov without any changes. If you have any requests to change, remove or update your study details, please contact register@clinicaltrials.gov. As soon as a change is implemented on clinicaltrials.gov, this will be updated automatically on our website as well.

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