In this randomized double-blind controlled study from Thailand, patients with dyspepsia were treated with a classic medication, with a combination and with a single dose of turmeric extract. This study appears to be the first direct comparison showing the efficacy of curcumin in the treatment of functional dyspepsia compared to omeprazole. As a result, curcumin was effective in all subtypes of functional dyspepsia. Curcumin and omeprazole were both effective in functional dyspepsia and did not appear to have a synergistic effect.
Introduction
In primary care, the initial approach to treating functional dyspepsia usually involves a combination of behavioral and dietary modifications as well as over-the-counter medications. Behavioral and dietary modifications aim to address triggers and lifestyle factors that may contribute to symptoms. Over-the-counter proton pump inhibitors (PPIs) are commonly recommended as first-line treatment in several countries.
If symptoms persist, dyspepsia is usually treated with omeprazole. The aim of this study was to demonstrate a possible alternative with the administration of a turmeric extract. Turmeric, scientifically known as Curcuma longa L., has been used intensively for a long time. This plant contains a valuable active ingredient, curcumin, which is used both externally and orally for medicinal purposes. Curcumin is often used in skin care creams and cosmetics, but is also available in the form of powder capsules, which are used to treat various gastrointestinal complaints, including dyspepsia. Recent results of a Cochrane review suggest that curcumin may provide a moderate improvement in dyspepsia symptoms compared to placebo.10 However, there is currently a lack of direct evidence for the efficacy of curcumin compared to conventional medications.
Methods
Study design
This multi-center, randomized, double-blind, placebo-controlled, parallel-group equivalence study was conducted at the Thai Traditional Medicine Institute and Chao Phraya Abhaibhubejhr Hospital from January 2019 to 2021. Patients participating in the study were randomly assigned to one of three groups: Curcumin plus omeprazole (C+O), curcumin only (C only) and omeprazole only (O only). The study results were published in accordance with the CONSORT (Consolidated Standards of Reporting Trials) guidelines and the CONSORT Herbal Extension.
Study population
Patients willing to participate in this study were screened for eligibility: Symptoms compatible with functional dyspepsia according to the Rome IV criteria, age between 18 and 70 years, Eastern Cooperative Oncology Group performance status 0 or 1 (indicating good general health), no intake of aspirin or non-steroidal anti-inflammatory drugs within the last three months, no intake of curcumin or curcumin-containing foods (approx. 250 mg daily) in the last 4 weeks prior to the study, no symptoms related to irritable bowel syndrome (such as constipation, diarrhea, and frequent bowel movements), no use of herbal medicines or medications that may affect gastrointestinal symptoms or disorders, and no use of PPIs in the last 4 weeks prior to the study. Exclusion criteria were: Pregnancy or breastfeeding, allergy to curcumin, presence of gallstones, severe inflammation of the gastric mucosa, esophageal mucosa or intestinal mucosa, previous infection with the gastric pathogen H. pylori, coexistence of diseases that could interfere with the treatment of functional dyspepsia, or presence of symptoms or physical signs suggestive of serious diseases incompatible with functional dyspepsia.
Treatment and safety protocol
The herbal medicine used in this study was curcumin, a natural compound from turmeric, also known as Curcuma longa L. It was administered in the form of powder capsules containing 250 mg curcumin. Before the study began, the curcumin capsules underwent qualitative testing to ensure their quality and purity, as well as compliance with regulatory requirements. Rigorous measurements were conducted to confirm the presence of curcumin and the absence of impurities or contaminants by the Herb and Thai Traditional Medicine Development, Department of Thai Traditional and Alternative Medicine, Ministry of Public Health.
Results
The recruitment phase for this study began on June 27, 2019, and the follow-up period ended on January 31, 2020. A total of 241 patients were screened for eligibility; 206 of them met the inclusion criteria and were enrolled and randomized into one of the three groups. The most common reason for non-participation was incompatibility with the diagnosis of functional dyspepsia, followed by incorrect age, recent PPI use, pregnancy or breastfeeding, current H. pylori infection and refusal to give consent. A total of 69, 69 and 68 patients were randomly assigned to groups C+O, C and O; of these, 16, 20 and 19 dropped out, respectively. The strength of the study lies in its relevance to daily clinical practice, as it offers further drug options in addition to PPIs, without additional side effects. It is the first well-designed study comparing curcumin with PPIs in functional dyspepsia, with confirmation by endoscopy and exclusion of H. pylori infection. Limitations of this study included the small number of patients who failed follow-up and the lack of long-term follow-up data. Future studies should investigate the long-term benefits and harms (at least 6-12 months) of curcumin in functional dyspepsia, the long-term use of curcumin when needed in functional dyspepsia, and the efficacy of curcumin in other functional gastrointestinal disorders.
Conclusion
Curcumin and omeprazole had comparable efficacy in functional dyspepsia, with no apparent synergistic effect.