The results of a prospective online survey on the effects of self-medication with organic grapefruit seed extract (here: CitroBiotic) were published in the renowned journal for phytotherapy. The study involved 100 people suffering from chronic gastrointestinal complaints. The study was conducted by the well-known naturopath Prof. Dr. Dr. Bernhard Uehleke. As a result, there were significant reductions based on defined symptom scores over the entire observation period of 56 days. Among the symptoms that improved were heartburn and other symptoms that are often reported in connection with reflux disease, indigestion, irritable bowel syndrome, leaky gut or intolerances.
In this exploratory longitudinal study, self-reports were collected from individuals who suffered from chronic gastrointestinal symptoms and sought relief through self-medication with a grapefruit seed extract (Bio-GKE – CitroBiotic). This is neither a clinical trial nor a non-interventional study, but an exploratory longitudinal study with self-reports. Data was collected online and there was no face-to-face contact with a doctor or study nurse. Participants followed their own decision to use GKE and to provide their data to a data retrieval system after consenting in accordance with applicable national data protection regulations. The test product was provided by the sponsor to ensure that the correct product was used for the intended observation period. Symptoms were documented 4-12 days (VA) prior to taking GKE on Day 1 and then on Day 1, Day 28, 42 and 56 of continuous oral dosing. New symptoms, predominant symptoms, bowel habits, amount of oral intake and overall status were recorded daily during the observation period. On day 56, some global assessments were also recorded. The evaluation cohort was to include at least 100 subjects, and within the survey cohort we were able to evaluate 100 subjects (15 m and 85 f). The total gastrointestinal symptom score decreased from a mean (± SD) of 78.7 ± 36.9 points on day 1 by 26.4% on day 14, by 53.1% on day 28, by 58.7% on day 42 and by 49.9% on day 56. Upper gastrointestinal symptoms such as heartburn improved better than lower GI symptoms (by 57.9 % compared to 47.3 % on day 56). Overall symptoms were rated as “very much improved” by 30%, “much improved” by 42%, “somewhat improved” or “unchanged” by 20% and “worsened” by 1%. GKE was well tolerated. Minor adverse events reported were considered by the authors to be most likely insignificant. More than half of the participants rated the intake as “very pleasant” or “pleasant” and intended to continue GKE beyond the observation period. In this prospective, uncontrolled study, GKE appeared to improve gastrointestinal symptoms as reported by users. These results need to be confirmed in controlled clinical trials to demonstrate the efficacy and tolerability of GKE in functional gastrointestinal disorders. Data collected from participants without personal contact carry a high risk of bias. The evaluation of self-treatment as presented here is clearly limited to marketed products and may provide interesting details of self-treatment outside the prescription setting.