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Completed

NCT Number: NCT05476549

Effects of Lemon Verbena Extract Supplementation in Sub-ADHD Children

The aim of this study is to investigate the effects of 15 mg/kg lemon verbena, in comparison to placebo, on the attention deficit hyperactivity disorder (ADHD) type behaviour and cognitive function of children who do not have a diagnosis of ADHD, but who exhibit high scores (highest tertile) on ADHD behaviour parameters. Multiple aspects of mood will also be assessed.

The proposed randomised, double-blind, placebo-controlled, parallel groups design methodology will assess the psychological effects of 15 mg/kg lemon verbena extract and a matched placebo prior to and after 4 and 8 weeks of supplementation. The trial will utilise the COMPASS cognitive assessment system (Northumbria University) and a range of mood measures during laboratory testing visits.

Parents and children will also take part in a concomitant smartphone study, comprising the collection of the parent's assessment of the child's behaviour/cognitive function and the child's self-report of the same, plus their mood. These assessments will take place on Days -1, 14, 28, 42 and 56.

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Key information

Conditions

Behavior, Child Behavior Child Behavior Cognitive Change

Age range

8 year–17 year

Sex eligibility

All sexes

Study type

Interventional

Phase

Not applicable

Primary location

Brain, Performance, Nutrition Research Centre, Northumbria University

Newcastle upon Tyne, Tyne & Wear, NE1 8ST, United Kingdom

Who can participate

Healthy volunteers accepted: Yes

Only the study team can determine whether someone qualifies for participation.

Inclusion criteria

  • Are in good health as reported by themselves and their parent/guardian
  • Are aged 8 to 17 years at the time of giving assent and parents giving consent
  • Have a sex and age-related BMI less than the 98th centile according to the local NHS guidelines
  • Are rated by their parents as having a high score (T score of ≥60) on both the Connors 3 subscales of Inattention and Hyperactivity/Impulsivity.
  • Have no current diagnosis of ADHD
  • Have no relevant food intolerances/ sensitivities/ allergies
  • Are not currently using any illicit, herbal or recreational drugs including alcohol and nicotine products
  • Are not currently taking prescription medications
  • Have not taken dietary supplements e.g. Vitamins, omega 3 fish oils etc. in the last 4 weeks
  • Do not have a diagnosed neurological condition, or learning/behavioural or neurodevelopmental differences (e.g. dyslexia, autism)
  • Do not suffer from visual (including colour blindness) impairment that cannot be corrected with glasses or lenses (that may impact task performance in the opinion of the PI).
  • Do not have any pre-existing diagnosed medical condition/illness which will impact taking part in the study
  • Consume less than 250 mg/day of caffeine.
  • Can complete all of the study assessments at the training visit
  • Are not currently participating in other clinical or nutrition intervention studies, or have in the past 4 weeks
  • Are compliant with regards to treatment consumption
  • Have not taken antibiotics within the past 4 weeks
  • Do not have any health condition that would prevent fulfilment of the study requirements (this includes non-diagnosed conditions for which no medication may be taken)

Treatment and study plan

Lemon verbena

Dietary Supplement

Lemon verbena supplement administered at an estimated daily dose of 15mg/kg

Placebo

Dietary Supplement

Placebo supplement containing carrier material only

Primary outcomes

  1. Change in Conners 3 score from baseline to 8 weeks, parent rating

    Time frame: Baseline to 8 weeks

  2. Change in Conners 3 score from baseline to 8 weeks, child rating

    Time frame: Baseline to 8 weeks

  3. Change in total mood disturbance from baseline to 8 weeks

    Time frame: Baseline to 8 weeks

    Profile of mood states questionnaire

  4. Change in depression-dejection from baseline to 8 weeks

    Time frame: Baseline to 8 weeks

    Profile of mood states questionnaire

  5. Change in tension-anxiety from baseline to 8 weeks

    Time frame: Baseline to 8 weeks

    Profile of mood states questionnaire

  6. Change in anger-hostility from baseline to 8 weeks

    Time frame: Baseline to 8 weeks

    Profile of mood states questionnaire

  7. Change in confusion-bewilderment from baseline to 8 weeks

    Time frame: Baseline to 8 weeks

    Profile of mood states questionnaire

  8. Change in vigour-activity from baseline to 8 weeks

    Time frame: Baseline to 8 weeks

    Profile of mood states questionnaire

  9. Change in fatigue-inertia from baseline to 8 weeks

    Time frame: Baseline to 8 weeks

    Profile of mood states questionnaire

  10. Change in systolic blood pressure from baseline to 8 weeks

    Time frame: Baseline to 8 weeks

    Systolic blood pressure (mmHg)

  11. Change in diastolic blood pressure from baseline to 8 weeks

    Time frame: Baseline to 8 weeks

    Diastolic blood pressure (mmHg)

  12. Change in body temperature from baseline to 8 weeks

    Time frame: Baseline to 8 weeks

    Degrees Celsius

  13. Change in RMSSD during the performance of cognitive tasks from baseline to 8 weeks

    Time frame: Baseline to 8 weeks

    Root mean square of successive differences between normal heartbeats (RMSSD)

  14. Change in heart rate during the performance of cognitive tasks from baseline to 8 weeks

    Time frame: Baseline to 8 weeks

    Beats per minute

  15. Change in heart rate variability index during the performance of cognitive tasks from baseline to 8 weeks

    Time frame: Baseline to 8 weeks

    Heart rate variability index

  16. Change in pNN50 during the performance of cognitive tasks from baseline to 8 weeks

    Time frame: Baseline to 8 weeks

    pNN50 is the mean number of times per hour in which the change in consecutive normal sinus (NN) intervals exceeds 50 milliseconds.

  17. Change in stress index during the performance of cognitive tasks from baseline to 8 weeks

    Time frame: Baseline to 8 weeks

    The stress index is a measure of the ratio between the parasympathetic and sympathetic tone. intervals exceeds 50 milliseconds.

  18. Change in subjective anxiety from baseline to 8 weeks

    Time frame: Baseline to 8 weeks

    State-trait anxiety inventory (STAI) total score

  19. Change in subjective perceived stress from baseline to 8 weeks

    Time frame: Baseline to 8 weeks

    Perceived stress scale (PSS) total score

  20. Change in subjective mood from baseline to 8 weeks, alertness

    Time frame: Baseline to 8 weeks

    Visual analogue scale composite score

  21. Change in subjective mood from baseline to 8 weeks, stress

    Time frame: Baseline to 8 weeks

    Visual analogue scale composite score

  22. Change in subjective mood from baseline to 8 weeks, tranquility

    Time frame: Baseline to 8 weeks

    Visual analogue scale composite score

  23. Change in speed of performance from baseline to 8 weeks

    Time frame: Baseline to 8 weeks

    Cognitive task composite score, milliseconds

  24. Change in accuracy of performance from baseline to 8 weeks

    Time frame: Baseline to 8 weeks

    Cognitive task composite score, %

  25. Change in accuracy of performance on arrow flankers task from baseline to 8 weeks

    Time frame: Baseline to 8 weeks

    Cognitive task score, %

  26. Change in accuracy of performance on numeric working memory task from baseline to 8 weeks

    Time frame: Baseline to 8 weeks

    Cognitive task score, %

  27. Change in accuracy of performance on Stroop task from baseline to 8 weeks

    Time frame: Baseline to 8 weeks

    Cognitive task score, %

  28. Change in accuracy of performance on Corsi blocks task from baseline to 8 weeks

    Time frame: Baseline to 8 weeks

    Cognitive task score, %

  29. Change in accuracy of performance on rapid visual information processing task from baseline to 8 weeks

    Time frame: Baseline to 8 weeks

    Cognitive task score, %

  30. Change in accuracy of performance on peg and ball task from baseline to 8 weeks

    Time frame: Baseline to 8 weeks

    Cognitive task score, number of errors

  31. Change in reaction time of performance on arrow flankers task from baseline to 8 weeks

    Time frame: Baseline to 8 weeks

    Cognitive task score, reaction time in milliseconds

  32. Change in reaction time of performance on numeric working memory task from baseline to 8 weeks

    Time frame: Baseline to 8 weeks

    Cognitive task score, reaction time in milliseconds

  33. Change in reaction time of performance on Stroop task from baseline to 8 weeks

    Time frame: Baseline to 8 weeks

    Cognitive task score, reaction time in milliseconds

  34. Change in reaction time of performance on rapid visual information processing task from baseline to 8 weeks

    Time frame: Baseline to 8 weeks

    Cognitive task score, reaction time in milliseconds

  35. Change in false alarms on rapid visual information processing task from baseline to 8 weeks

    Time frame: Baseline to 8 weeks

    Cognitive task score, number of false alarms

  36. Change in completion time of peg and ball task from baseline to 8 weeks

    Time frame: Baseline to 8 weeks

    Cognitive task score, time in milliseconds

  37. Change in thinking time of peg and ball task from baseline to 8 weeks

    Time frame: Baseline to 8 weeks

    Cognitive task score, time in milliseconds

Sponsors and collaborators

Lead sponsor

Northumbria University

Other

Collaborators

  • Finzelberg GmbH

Registry information

Official study title

Effects of Lemon Verbena Extract Supplementation on Behaviour Mood and Cognitive Function in Sub-ADHD Children

Important dates

Study start
2022
Primary completion
2023
Study completion
2023
First posted
Jul 27, 2022
Registry last updated
Dec 11, 2023

OpenTrials presents study information sourced from ClinicalTrials.gov. The official registry record should be consulted for the latest information.

View the official ClinicalTrials.gov record (opens in a new tab)

This listing is for discovery and informational purposes only. It is not medical advice, does not guarantee that a study is recruiting, and does not determine eligibility. Contact the study team and a qualified healthcare professional when considering participation.

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