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Trial registered on ANZCTR

Registration number
Ethics application status
Date submitted
Date registered
Date last updated
Type of registration
Prospectively registered

Titles & IDs
Public title
Does melatonin help children with Attention Deficit Hyperactivity Disorder (ADHD) sleep better?
Scientific title
Does melatonin reduce sleep onset latency compared to placebo in children with ADHD on stimulant medication?
Secondary ID [1] 284552 0
Universal Trial Number (UTN)
Trial acronym
Linked study record

Health condition
Health condition(s) or problem(s) studied:
Insomnia 291816 0
ADHD 291942 0
Condition category
Condition code
Mental Health 292180 292180 0 0
Other mental health disorders

Study type
Description of intervention(s) / exposure
This study will use a randomised, double-blinded N-of-1 trial design comparing the effects of melatonin and placebo on reducing sleep latency in individual subjects.

The intervention medication will be immediate release melatonin taken orally 30 min before bedtime; 3 mg if child is under 40 kg, and 6 mg if child is equal to or over 40 kg.

The comparator medication will be an equivalent placebo tablet, containing cellulose.

Each participant will undergo three treatment periods, consisting of one week of melatonin and one week of placebo in randomized order, for a total of 6 weeks. The first day of data from each week will be discarded to allow for washout.

Adherence will be monitored by pill counts at the end of the trial.
Intervention code [1] 289318 0
Treatment: Drugs
Intervention code [2] 289319 0
Treatment: Other
Comparator / control treatment
Identical placebo tablet (containing cellulose)
Control group

Primary outcome [1] 292059 0
Mean change in sleep onset latency (SOL) (min) as measured by parent-completed sleep diaries
Timepoint [1] 292059 0
Average of data recorded nightly during each treatment period by the parent
Secondary outcome [1] 308104 0
Mean change in SOL (min), measured by actigraphy
Timepoint [1] 308104 0
Average of data recorded nightly during each treatment period by the parent
Secondary outcome [2] 308105 0
Mean amount of time awake during the night as estimated by sleep diary and actigraphy
Timepoint [2] 308105 0
Average of data recorded nightly during each treatment period by the parent
Secondary outcome [3] 308106 0
Mean duration of sleep (min) while in bed, measured by sleep diaries and actigraphy
Timepoint [3] 308106 0
average of data recorded nightly during each treatment period of one week by the parent
Secondary outcome [4] 308107 0
Number of awakenings after sleep onset, measured by sleep diaries
Timepoint [4] 308107 0
Average of data recorded nightly during each treatment period by the parent
Secondary outcome [5] 345172 0
Mean change in Child Sleep Habits Questionnaire Scores (CHSQ) scores
Timepoint [5] 345172 0
At the end of each treatment period

Key inclusion criteria
1. Children and adolescents between 6 and 17 years.

2. Diagnosis of ADHD according to DSM- IV or V criteria.

3. On a stable dose of stimulant (e.g., Ritalin (registered trademark), Ritalin LA, Concerta (registered trademark) for at least 1 month prior to the study.

4. SOL of 45 min or more, 3 or more nights/week, for 1 month or more as confirmed by parent/guardian.

5. If previously on melatonin, have ceased it at least two weeks previously.

6. Informed consent by parent/guardian and by child (if 12 years and over).
Minimum age
6 Years
Maximum age
17 Years
Both males and females
Can healthy volunteers participate?
Key exclusion criteria
1. Children with co-morbid psychiatric/neurological diagnoses that may affect sleep, including:
a) autism/pervasive development disorder
b) brain injury
c) cerebral palsy
d) uncontrolled major depression
e) migraines
f) posttraumatic stress disorder
g) psychosis or schizophrenia
h) seizure disorder (i.e. seizure in the last 12 months)

2. Children with any of the following disorders of sleep:
a) Untreated Obstructive Sleep Apnea
b) Untreated Sleep Related Breathing Disorder (any form of trouble during sleep associated with breathing, such as need for oxygen, underlying lung disease outside of stable asthma)
c) Untreated narcolepsy
d) Sleep related movement disorders (head banging or body rocking that results in insomnia)
e) Parasomnias (current, regular sleep walking or night terrors)
f) Adjustment insomnia (acute – related to hospitalization, travel etc)
g) Insomnia due to drug use, or mental health issue
h) Secondary enuresis

3. Known allergy or hypersensitivity to melatonin or other study drug ingredients; Mannitol, Dextrose, Cellulose, Crospovidone, Calcium Carbonate, Xylitol, Dicalcium Phosphate, Vegetable Stearic Acid, Vegetable Magnesium Stearate, Silica
4. Children on immunosuppressive drugs, blood pressure drugs, SSRIs or anticoagulant drugs;
5. Children not on regular sedatives or hypnotics whose parents do not agree not to commence these treatments regularly during the course of the trial.
6. Parents of children on sedatives or hypnotics who do not agree not to alter the daily dose of these for the duration of the trial.
7. Patients with active or uncontrolled hormonal disorders, or diabetes, or active liver disease, or abnormal kidney function or untreated kidney disease, or any blood clotting disorders;
8. Participants who disagree to not driving or operating heavy machinery within 8 hours of ingestion of study medication;
9. Breastfeeding or pregnant women
10. Girls 12 years and above who are menstruating and sexually active;
11. Children whose parent/primary caregiver does not understand English, or have a phone.

Study design
Purpose of the study
Allocation to intervention
Randomised controlled trial
Procedure for enrolling a subject and allocating the treatment (allocation concealment procedures)
Methods used to generate the sequence in which subjects will be randomised (sequence generation)
Masking / blinding
Blinded (masking used)
Who is / are masked / blinded?
The people receiving the treatment/s
The people administering the treatment/s
The people assessing the outcomes
The people analysing the results/data
Intervention assignment
Other design features
Each individual participant will undergo a N-of-1 trial.
Data from the first treatment period from each subject will form a RCT.
The data from individual N-of-1 trials will be aggregated and compared with the RCT.
Phase 4
Type of endpoint(s)
Statistical methods / analysis

Recruitment status
Date of first participant enrolment
Date of last participant enrolment
Date of last data collection
Sample size
Accrual to date
Recruitment in Australia
Recruitment state(s)
Recruitment hospital [1] 2420 0
Mater Children's Hospital - South Brisbane

Funding & Sponsors
Funding source category [1] 289179 0
Government body
Name [1] 289179 0
Address [1] 289179 0
National Health and Medical Research Council
GPO Box 1421
Canberra ACT 2601
Country [1] 289179 0
Primary sponsor type
The University of Queensland
The University of Queensland
Brisbane QLD 4072 Australia
Secondary sponsor category [1] 287848 0
Name [1] 287848 0
Address [1] 287848 0
Country [1] 287848 0

Ethics approval
Ethics application status
Ethics committee name [1] 290959 0
Mater Health Services HREC
Ethics committee address [1] 290959 0
Ethics committee country [1] 290959 0
Date submitted for ethics approval [1] 290959 0
Approval date [1] 290959 0
Ethics approval number [1] 290959 0
HREC 14/MHS/28

Brief summary
Methodology Randomised, Double-Blind, Placebo-Controlled, Multi-Centre trial of aggregated N-of-1 Trials compared to parallel group RCT on the Effects of melatonin on SOL in children and adolescents with ADHD who are receiving stimulant medication.
Study Duration 6 weeks (3 pairs over a six week period) for each individual participant
Objectives Hypotheses:
1) Melatonin is effective for alleviating initial insomnia in ADHD children who are receiving stimulant medication; and
2) N-of-1 trials provide a similar estimate of treatment effect with less uncertainty than a parallel group RCT.

1) To determine the efficacy of melatonin in shortening sleep latency times in children with ADHD treated with stimulants

2) To determine whether n-of-1 trials provide similar estimate of treatment effect with less uncertainty than a parallel group RCT
Number of Participants 300 participants (children), 300 parent/guardians from Queensland and Canada
Trial website
Trial related presentations / publications
Public notes

Principal investigator
Name 48146 0
Dr Jane Nikles
Address 48146 0
School of Medicine
The University of Queensland
12 Salisbury Rd
Ipswich 4305
Country 48146 0
Phone 48146 0
61 7 3381 1597
Fax 48146 0
Email 48146 0
Contact person for public queries
Name 48147 0
Dr Jane Nikles
Address 48147 0
School of Medicine
The University of Queensland
12 Salisbury Rd
Ipswich 4305
Country 48147 0
Phone 48147 0
61 7 3381 1597
Fax 48147 0
Email 48147 0
Contact person for scientific queries
Name 48148 0
Dr Jane Nikles
Address 48148 0
School of Medicine
The University of Queensland
12 Salisbury Rd
Ipswich 4305
Country 48148 0
Phone 48148 0
61 7 3381 1597
Fax 48148 0
Email 48148 0

No information has been provided regarding IPD availability
Summary results
No Results