Stress Study

Are you looking to reduce your stress levels?

MIgraine Study

If you are aged over 18 years and are experiencing mild to moderate stress, you could help assess the effectiveness of a herbal product called Caralluma.

Thank you for your interest in a new study being conducted by RDC Clinical which is evaluating the effectiveness of a herbal extract (in capsule form) on stress levels. We are looking for healthy adults aged over 18 years that are living in Brisbane (or surrounds).

If you are feeling mildly to moderately stressed, we would love to hear from you. You can make a difference by helping to investigate a more natural alternative for reducing stress and improving sleep without the use of more common pharmacological therapies.

How long is the study, and when does it start?

The study will involve approximately 100 adults aged over 18 years, who will each participate for a period of 8 weeks.

To make the timings of these visits as convenient as possible for you, we are recruiting on a rolling basis which means that your individual start date is flexible. Your involvement in this study will be 8 weeks and you will be required to come into our clinic 3 times: at the beginning, middle and end of the study.

Please see below for more information. You can find the eligibility and registration forms at the bottom of the page.

About the supplement you’ll help test…

The investigational product is a commercially available capsule-form extract of Caralluma fimbriata plant (Caralluma). Previous research has shown the product to have beneficial effects on reducing anxiety at a 1g per day dose. All clinical studies, to date, found the product to be safe for use with no serious adverse effects associated with its oral administration. This study aims to investigate the efficacy of this Caralluma extract in improving symptoms of stress such as poor sleep, agitation, feeling overwhelmed or constant worrying.

The natural herbal extract will be taken as a 500 mg total daily dose in capsule form (2 capsules per day).

As this study is placebo-controlled, you may or may not be allocated the active product. 50% of participants will be assigned the placebo (a harmless inactive substance typically used as an additive in food production). During the study period, neither you nor the study investigators will know which product you have been allocated.

Why is this study being conducted?

The aim of this study is to assess the effectiveness of Caralluma fimbriata on stress, sleep and neurotransmitters in a healthy adult population over an 8 week period.

In Australia, anxiety disorders affect an estimated one in eight women and one in ten men, thus highlighting anxiety as the most prevalent mental health condition in the country.

These figures only increase when they include people who experience subclinical anxiety but have not been diagnosed with a disorder. There is a growing understanding that stress and subclinical anxiety also reduce quality of life, and contribute to physical illness such as high blood pressure and cardiovascular disease.

Pharmaceutical treatments for anxiety come with the risk of adverse effects such as diarrhea and nausea, habituation, dependency and withdrawal, and have low efficacy for subclinical presentations. Therefore, the need for alternatives, specifically for sub-clinical anxiety and stress has grown.

Caralluma is a succulent plant that grows from India to North Africa. Results of a human clinical study on 1g of extract daily indicated a significant reduction in anxiety.

This current study has been designed to further assess the effects of Caralluma fimbriata extract on stress (sub-clinical anxiety) at a lower dose (500mg). It will also measure the effect on sleep and explore the mechanism of action by testing neurotransmitters.

What is required of participants?

Your involvement in the study will be 8 weeks. During this time, you will be required to take the study product each day (2 capsules a day), and complete certain assessments at the beginning, middle and end of the study so that we can assess the effectiveness of the study product.

3 x Clinic Appointments

Most of the study requirements can be completed at home; however, you will be required to attend our clinic 3 times during the study (beginning, week 4 and week 8). We ask you to attend the clinic so that we can collect a small blood sample, check your blood pressure and you can drop off your saliva samples.

Summary of assessments occurring at the beginning, week 4 and week 8 of the study:

  • online questionnaires about your stress levels, mood and sleep habits (completed either at home or in clinic)
  • height, weight, and waist circumference (measured in clinic)
  • blood pressure (measured in clinic)
  • blood test for various stress hormones (taken in clinic)
  • saliva test for cortisol (via a home collection kit)

The information we collect during the study will enable the investigators to assess the product’s effectiveness on reducing stress levels and improving sleep over the 8-week study period.


You will be eligible for a $100 reimbursement to cover your time and any out-of-pocket expenses incurred in attending clinic visits. The payment will be made via direct deposit to your nominated bank account once all study requirements (8 weeks participation) have been met.

If you are a healthy adult and would like to participate, we’d love to hear from you. Please register your interest by answering the questionnaire and completing the form on this page…we’ll then get in touch to screen you for eligibility.

Check if you can take part… study participant requirements.

Check if you can take part… study participant requirements.

  • Aged over 18 years
  • Experiencing feelings of mild to moderate stress (such as poor sleep, agitation, feeling overwhelmed or constant worrying).
  • Not currently receiving treatment for anxiety (eg. medication, counselling)
  • Generally healthy with no uncontrolled serious illnesses
  • A non-smoker
  • Not suffering from any unstable or serious illness
  • Willing to keep your diet and exercise routine the same whilst on the study
  • Able to commit to the study for the 8-week period and attend 3 clinic visits during that time

Please register your interest by answering the questionnaire and completing the form on this page… we’ll then get in touch to screen you for suitability.



Ethics approval & privacy… you’ll be in safe, professional hands.

This RDC Clinical study has been approved by the National Institute of Integrative Medicine Human Research Ethics Committee under Approval Number: 0091E_2021. The study is also registered on under Registration Number NCT05232266.

Trained Trial Co-ordinators will supervise your progress throughout the study. Your results will be made available to you at the conclusion of the study. Any of your personal information collected during the study will be kept in the strictest confidence.

About the location of the'll attend clinic appointments

The RDC Clinic is located at 76 Doggett Street, Newstead, Brisbane. Our clinic is open from 6.30am to 6pm M-F and have Saturday appointments available from 6.30am. 

We are walking distance from the Commercial Road Ferry Terminal & local buses, and a quick 10-minute walk from Bowen Hills train station. 

We also have free onsite visitor parking available.