Zeitschrift für Phytotherapie 2024; 45(02): 54-60
DOI: 10.1055/a-2194-2206
Peer Review

Grapefruit Seed Extract Reduces Gastrointestinal Symptoms

Results of a Prospective Online Survey on Effects of Self-treatment
Bernhard Uehleke
1   Clinical Evidence Evaluations UG, Online-Research-Institute, Berlin, Germany
,
Martin Storr
2   Center of Endoscopy, Starnberg, Germany
3   Medical Clinic II, Ludwig-Maximilians-University, Munich, Germany
,
Martin Hörning
4   Institut fuer Gesundheitsforschung und Soziale Psychiatrie, Catholic University of Applied Sciences, Paderborn, Germany
› Author Affiliations

Abstract

In this explorative longitudinal survey, self-reported data was collected from persons suffering from chronic gastrointestinal symptoms, who were seeking relief employing self-medication with a grapefruit seed extract (GKE). This is not a clinical trial nor a non-interventional study, but an explorative longitudinal survey with self-reports. The data was collected online and there were no personal contacts with a physician or a study nurse. Participants followed their own decision to use GKE and to provide their data to a data retrieval system, following informed consent according to existing national regulations on data protection. The test product was provided by the sponsor to make sure that the correct product was used for the intended observation period.

Drop in criteria were chronic gastrointestinal symptoms, including those of functional dyspepsia (FD, resp. non-ulcer dyspepsia NUD) and/or irritable bowel syndrome (IBS) for more than 4 weeks, resulting in a score of an expanded Nepean Index (‘total gastrointestinal score’) higher than 20. Symptoms were documented 4–12 days (VA) prior to GKE use on day 1 and then on day 1, days 28, 42 and 56 of continuous oral use. New symptoms, predominating symptoms, stool habits, amount of oral intake and global status was retrieved every day during the observation period. On day 56 some global assessments were additionally recorded.

The evaluation cohort was intended to be at least 100, and within the survey cohort we were able to evaluate 100 subjects (15 m and 85 f). Total gastrointestinal symptom score decreased from a mean (±SD) of 78.7±36.9 points 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, when compared to day 1. Upper gastrointestinal symptoms like heartburn improved better compared to lower GI symptoms (by 57.9% versus 47.3% on day 56). Overall complaints were rated as “very strongly improved” by 30%, “strongly improved” by 42%, “somewhat improved” or “unchanged” by 20% and as “deteriorated” by 1%. GKE was tolerated well. Minor adverse events reported were judged as most probably unrelated by the authors. 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 survey, GKE seemed to improve GI-symptoms, based on users reports. These results need to be confirmed in controlled clinical trials proofing efficacy and tolerance of GKE in functional GI-diseases. Data collected from participants without any personal contact bear a high risk of bias. Evaluation of self-treatment as presented here is clearly restricted to marketed products and may report interesting details of self-treatment outside prescription settings.



Publication History

Article published online:
25 April 2024

© 2024. Thieme. All rights reserved.

Georg Thieme Verlag KG
Rüdigerstraße 14, 70469 Stuttgart, Germany

 
  • References

  • 1 Madisch A, Andresen V, Enck P. et al. The diagnosis and treatment of functional dyspepsia. Dtsch Arztebl Int 2018; 115: 222-232 DOI: 10.3238/arztebl.2018.0222.
  • 2 Huang KY, Wang FY, Lv M. et al. Irritable bowel syndrome: Epidemiology, overlap disorders, pathophysiology and treatment. World J Gastroenterol 2023; 29: 4120-4135 DOI: 10.3748/wjg.v29.i26.4120.
  • 3 von Wulffen M, Talley NJ, Hammer J. et al. Overlap of irritable bowel syndrome and functional dyspepsia in the clinical setting: prevalence and risk factors. Dig Dis Sci 2019; 64: 480-486 DOI: 10.1007/s10620-018-5343-6.
  • 4 Talley NJ, Dennis EH, Schettler-Duncan VA. et al. Overlapping upper and lower gastrointestinal symptoms in irritable bowel syndrome patients with constipation or diarrhea. Am J Gastroenterol 2003; 98: 2454-2459 DOI: 10.1111/j.1572-0241.2003.07699.x.
  • 5 Neumann H, Monkemuller K, Kandulski A. Malfertheiner P. Dyspepsia and IBS symptoms in patients with NERD, ERD and Barrett's esophagus. Dig Dis 2008; 26: 243-247 DOI: 10.1159/000121354.
  • 6 Reimer C, Søndergaard B, Hilsted L, Bytzer P. Proton-pump inhibitor therapy induces acid-related symptoms in healthy volunteers after withdrawal of therapy. Gastroenterology 2009; 137: 80-87.e1 DOI: 10.1053/j.gastro.2009.03.058.
  • 7 Labenz C, Madisch A, Labenz J. Reizmagensyndrom in der Hausarztpraxis: Therapeutische Vielfalt oder Hilflosigkeit? [Functional dyspepsia in primary care: therapeutic variety or helplessness?]. MMW Fortschr Med 2019; 161: 15-19 DOI: 10.1007/s15006-019-0289-y.
  • 8 Saller R, Iten F, Reichling J. Dyspeptische Beschwerden und Phytotherapie – eine Übersicht über traditionelle und moderne Phytotherapeutika. [Dyspeptic pain and phytotherapy--a review of traditional and modern herbal drugs]. Forsch Komplementarmed Klass Naturheilkd 2001; 8: 263-273 DOI: 10.1159/000057236.
  • 9 Ingrosso MR, Ianiro G, Nee J. et al. Systematic review and meta-analysis: efficacy of peppermint oil in irritable bowel syndrome. Aliment Pharmacol Ther 2022; 56: 932-941 DOI: 10.1111/apt.17179.
  • 10 Madisch A, Frieling T, Zimmermann A. et al. Menthacarin, a proprietary peppermint oil and caraway oil combination, improves multiple complaints in patients with functional gastrointestinal disorders: a systematic review and meta-analysis. Dig Dis 2023; 41: 522-532 DOI: 10.1159/000528553.
  • 11 Malfertheiner P. STW 5 (Iberogast) therapy in gastrointestinal functional disorders. Dig Dis 2017; 35: 25-29 DOI: 10.1159/000485410.
  • 12 Han HW, Kwak JH, Jang TS. et al. Grapefruit seed extract as a natural derived antibacterial substance against multidrug-resistant bacteria. Antibiotics (Basel) 2021; 10: 85 DOI: 10.3390/antibiotics10010085.
  • 13 Song YJ, Yu HH, Kim YJ. et al. Anti-biofilm activity of grapefruit seed extract against Staphylococcus aureus and Escherichia coli . J Microbiol Biotechnol 2019; 29: 1177-1183 DOI: 10.1041/jmb.1905.05022.
  • 14 Kang S, Guo Y, Rao J. et al. In vitro and in vivo inhibition of Helicobacter pylori by Lactobacillus plantarum pH3A, monolaurin, and grapefruit seed extract. Food Funct 2021; 12: 11024-11032 DOI: 10.1039/d1fo01480c.
  • 15 Tsutsumi-Arai C, Takakusaki K, Arai Y. et al. Grapefruit seed extract effectively inhibits the Candida albicans biofilms development on polymethyl methacrylate denture-base resin. PLoS One 2019; 14: e0217496 DOI: 10.1371/journal.pone.0217496.
  • 16 Avula B, Sagi S, Wang YH. et al. Liquid chromatography-electrospray ionization mass spectrometry analysis of limonoids and flavonoids in seeds of grapefruits, other Citrus species, and dietary supplements. Planta Med 2016; 82: 1058-1069 DOI: 10.1055/s-0042-107598.
  • 17 Avula B, Dentali S, Khan IA. Simultaneous identification and quantification by liquid chromatography of benzethonium chloride, methyl paraben and triclosan in commercial products labeled as grapefruit seed extract. Pharmazie 2007; 62: 593-596
  • 18 Uehleke B, Wöhling H, Stange R. Eine prospektive «Fernstudie» (Study by Correspondence) über die Wirkung der Kneipp Hydrotherapie bei Patienten mit Beschwerden infolge einer Polyneuropathie. Schweizerische Z Ganzheitsmed / Swiss J Integr Med 2006; 20: 287-291 DOI: 10.1159/000286300.
  • 19 Meier L, Stange R, Michalsen A, Uehleke B. Clay jojoba oil facial mask for lesioned skin and mild acne – results of a prospective, observational pilot study. Forsch Komplementmed 2012; 19: 75-79 DOI: 10.1159/000338076.
  • 20 Uehleke B, Ortiz M, Stange R. Silicea gastrointestinal gel improves gastrointestinal disorders: a non-controlled, pilot clinical study. Gastroenterol Res Pract 2012; 2012: 750750 DOI: 10.1155/2012/750750.
  • 21 Forssmann K, Meier L, Uehleke B. et al. A non-interventional, observational study of a fixed combination of pepsin and amino acid hydrochloride in patients with functional dyspepsia. BMC Gastroenterol 2017; 17: 123 DOI: 10.1186/s12876-017-0675-9.
  • 22 Madisch A, Schaper S, Stange R, Uehleke B. Wirksamkeit der Luvos-Heilerde bei dyspeptischen und reizdarmtypischen Symptomen – Ergebnisse einer prospektiven nicht-interventionellen Studie. Abstract 127. Kongress der Deutschen Gesellschaft für Innere Medizin. 2020 in Wiesbaden
  • 23 Talley NJ, Verlinden M, Jones M. Validity of a new quality of life scale for functional dyspepsia: a United States multicenter trial of the Nepean Dyspepsia Index. Am J Gastroenterol 1999; 94: 2390-2397 DOI: 10.1111/j.1572-0241.1999.01363.x.
  • 24 Talley NJ, Haque M, Wyeth JW. et al. Development of a new dyspepsia impact scale: the Nepean Dyspepsia Index. Aliment Pharmacol Ther 1999; 13: 225-235 DOI: 10.1046/j.1365-2036.1999.00445.x.
  • 25 Storr M, Weigmann H, Landes S, Michel MC. Self-medication for the treatment of abdominal cramps and pain – a real-life comparison of three frequently used preparations. J Clin Med 2022; 11: 6361 DOI: 10.3390/jcm11216361.
  • 26 Krammer H, Storr M, Madisch A, Riffel J. Reizdarmbehandlung mit Lactobacillus plantarum 299v: Längere Einnahme verstärkt Behandlungserfolg – Ergebnisse einer nichtinterventionellen Studie [Treatment of IBS with Lactobacillus plantarum 299v: Therapeutic success increases with length of treatment – real-life data of a non-interventional study in Germany]. Z Gastroenterol 2021; 59: 125-134 DOI: 10.1055/a-1340-0204.
  • 27 Layer P, Andresen V, Allescher H. et al. Update S3-Leitlinie Reizdarmsyndrom: Definition, Pathophysiologie, Diagnostik und Therapie. Z Gastroenterol 2021; 59: 1323-1415 DOI: 10.1055/a-1591-4794.
  • 28 Tack J. et al. United European Gastroenterology (UEG) and European Society for Neurogastroenterology and Motility (ESNM) consensus on functional dyspepsia. United European Gastroenterol J 2021; 9: 307-331 DOI: 10.1002/ueg2.12061.