The use of Neuromodulators is now recognized by international consensus as effective in improving Disorders of Gut-Brain Interaction (DGBIs). However, the digestive mind-body concept of therapeutic drugs is still in the experience-based treatment stage, and there is a lack of clinical studies in the field of DGBIs. Although numerous studies have been conducted to confirm the safety of Neuromodulators for the treatment of DGBIs, the current functional dyspepsia (FD) treatment is still awaiting further explorations and accumulations. In addition, neuromodulators, like Flupentixol-Melitracen (FM), are often used as a second-line treatment option for FD after the failure of acid-suppressive therapy with proton pump inhibitors, etc. However, the efficacy of conventional drugs for FD is mediocre, which often leads to recurrent and prolonged symptoms, seriously affecting patients' confidence in treatment and their quality of life, and the repeated visits to the clinic also create a huge economic burden for the society. Therefore, we conducted a clinical trial to verify whether FM can be used as the first-line therapy to improve the efficacy of FD patients.

Inclusion Criteria:

1. adult patients with primary FD who meet the diagnostic criteria for Roman IV;
2. able to complete the questionnaire, trial evaluation and sign the written informed consent.

Exclusion Criteria:

1. organic gastrointestinal diseases by gastroenteroscopy within 6 months;
2. severe insufficiency of heart, liver, kidney, lung and other important organs and with congenital diseases;
3. allergic to the drugs used in this study
4. being pregnant, lactating or planning to become pregnant;
5. are taking or have taken monoamine oxidase inhibitors within the past 5 weeks;
6. have a known risk of narrow angle glaucoma.