Pharmacokinetics of Melatonin Administered in Oral, Lotion, and Bubble Bath Formulations

Melatonin is a hormone that promotes sleep that is available without a prescription in the United States. In addition to oral supplements, melatonin can be purchased in the form of lotions and bubble baths with unknown dosage and no frequency or age recommendations. In this study, researchers will examine how quickly melatonin in lotion and bubble bath is absorbed compared to oral tablets, as well as how long the melatonin lasts in the body.

Study Overview

• Status: Completed
• Conditions: Sleep
• Intervention / Treatment: Dietary supplement: Melatonin

Detailed Description

Melatonin is a hormone that promotes sleep that is available without a prescription in the United States. In addition to oral supplements, melatonin can be purchased in the form of lotions and bubble baths with unknown dosage and no frequency or age recommendations. A previous study (unpublished) has shown that a small amount of an over-the-counter lotion increases salivary melatonin levels by up to 1000 fold, a startling amount. Researchers will characterize the time course of the absorption and metabolism of lotion- and bubble bath-based melatonin compared to oral tablets in healthy 18-22 year olds.

The peak level, time to peak level and half-life of melatonin will be compared between the administration routes using a within-person (repeated measures) design and saliva sampling over 48 hours. Participants can choose specific days to participate within a one-month window, with a maximum of four sampling periods. All participants will collect control saliva samples (no melatonin treatment) one night at 10 PM and 4 AM. Participants will be asked to have two treatments 1) oral melatonin and 2) either lotion melatonin or bubble-bath melatonin. Participants can indicate if they have a preference for lotion vs. bubble bath or if they are willing to undergo both lotion and bubble bath treatments (adding a fourth sampling period). Order will be randomized.

For the treatments, saliva sampling times are as follows: Prior to melatonin administration (10 AM), then 15 min, 30 min, 45 min, 60 min, 90 min, 2 hours, 3 hours, 4 hours, 6 hours, 8 hours, 12 hours (10 PM), 18 hours (4 AM), 24 hours, 36 hours, and 48 hours after administration. Samples will be frozen at the participant's home until returned to the researchers at a later date. Melatonin in saliva samples will be quantitated via Enzyme Linked Immunosorbent Assay.

• Study Type: Interventional
• Enrollment (Actual): 12
• Phase: Not Applicable

Contacts and Locations

Study Locations

• United States
  • California
    • Redlands, California, United States, 92373
      • University of Redlands

Participation Criteria

Eligibility Criteria

• Ages Eligible for Study: Adult
• Accepts Healthy Volunteers: Yes

Description

Inclusion Criteria:

• University of Redlands student

Exclusion Criteria:

• Allergies or sensitivities to scented lotions or bath products
• Pregnancy

Study Plan

How is the study designed?

Design Details

• Primary Purpose: Basic Science
• Allocation: Randomized
• Interventional Model: Crossover Assignment
• Masking: None (Open Label)

Number of Arms

3

Arms and Interventions

Participant Group / Arm	Intervention / Treatment
Active Comparator: Oral tablet; 3 mg Tablets (Nature Made). Participants will need to fast for 2 hours prior to consumption and 2 hours after consumption.	Dietary supplement: Melatonin; Melatonin will be administered in three different forms
Experimental: Lotion; Dr. Teal's Sleep Lotion with Melatonin, Lavender, and Chamomile. 3 g lotion applied to one arm (without washing for at least 4 hours).	Dietary supplement: Melatonin; Melatonin will be administered in three different forms
Experimental: Bubble bath; Dr. Teal's Sleep Bath with Melatonin, Lavender, and Chamomile. 40L warm tap water maintained between 36.5 - 40 degrees C (98 - 104 degrees F) and 2 ml bubble bath. Participants will soak their feet and legs in the cooler for 15 minutes and then dry off (without rinsing or washing for at least 4 hours).	Dietary supplement: Melatonin; Melatonin will be administered in three different forms

What is the study measuring?

Primary Outcome Measures

Outcome Measure	Measure Description	Time Frame
Salivary melatonin level	assessed via ELISA	from immediately prior to administration to 48 hours post administration

Secondary Outcome Measures

Outcome Measure	Measure Description	Time Frame
Side effects	Frequency of headache, drowsiness, dizziness, skin irritation, vivid dreams, and nightmares	from immediately prior to administration to 48 hours post administration

Collaborators and Investigators

• Sponsor: University of Redlands
• Investigators: Principal Investigator: Lisa E Olson, Ph.D., University of Redlands

Study record dates

Study Major Dates

• Study Start (Actual): May 19, 2024
• Primary Completion (Actual): July 31, 2024
• Study Completion (Actual): July 31, 2024

Study Registration Dates

• First Submitted: April 19, 2024
• First Submitted That Met QC Criteria: April 19, 2024
• First Posted (Actual): April 24, 2024

Study Record Updates

• Last Update Posted (Actual): October 8, 2024
• Last Update Submitted That Met QC Criteria: October 3, 2024
• Last Verified: April 1, 2024

More Information

Terms related to this study

• Keywords: transdermal; melatonin; pharmacokinetics; oral
• Additional Relevant MeSH Terms: Physiological Effects of Drugs; Molecular Mechanisms of Pharmacological Action; Central Nervous System Depressants; Protective Agents; Antioxidants; Melatonin
• Other Study ID Numbers: 2024-002

Plan for Individual participant data (IPD)

• Plan to Share Individual Participant Data (IPD)?: YES
• IPD Plan Description: Upload salivary melatonin levels and side effect frequencies (all collected IPD) to National Sleep Research Resource (https://sleepdata.org/)
• IPD Sharing Time Frame: After relevant publication. Data will remain at the National Sleep Research Resource following their policy for keeping records.
• IPD Sharing Access Criteria: According to the National Sleep Research Resource
• IPD Sharing Supporting Information Type: STUDY_PROTOCOL; ICF

Drug and device information, study documents

• Studies a U.S. FDA-regulated drug product: No
• Studies a U.S. FDA-regulated device product: No
• product manufactured in and exported from the U.S.: No