Clinical Observation of Music Therapy Combined with Acupoint Application for the Treatment of Functional Constipation

Summary

This study aims to explore the clinical efficacy of music therapy combined with acupoint application based on the theory of midnight-noon ebb-flow in the treatment of functional constipation. Results show that this combination can effectively improve the constipation symptoms and quality of life of patients while ensuring safety.

Abstract

This study assessed the clinical efficacy of combining five-tone therapy with acupoint application, guided by the TCM midnight-noon ebb-flow theory, for treating functional constipation (FC). A total of 103 FC patients were divided into a study group (n=52) and a control group (n=51). The control group received oral polyethylene glycol with routine diet and exercise. The study group received additional five-tone therapy and acupoint application. Results showed that post-intervention, both groups exhibited improvements in defecation frequency, abdominal distension, and abdominal pain (p < 0.05). The study group demonstrated superior outcomes, showing significant improvements in Bristol Stool Scale (BSFS) classification and anal obstruction, and a markedly shorter time to first defecation compared to the control group (p < 0.001). Furthermore, all Patient Assessment of Constipation Symptoms (PAC-SYM) and quality-of-life scores in the study group were significantly lower than those in the control group (p < 0.001), indicating greater symptom relief and enhanced well-being. The intervention was found to be safe, with no statistically significant difference in the incidence of adverse reactions between the two groups (p = 0.400). The study concludes that five-tone therapy combined with acupoint application based on the midnight-noon ebb-flow theory is an effective and safe intervention. It can significantly alleviate constipation symptoms and improve the quality of life for patients with FC.

Introduction

Functional constipation (FC) is a common intestinal disease characterized by difficulty in defecation, decreased frequency of defecation and incomplete defecation¹. As a functional disease, its diagnosis requires the exclusion of conditions that may cause secondary constipation, such as constipation-predominant irritable bowel syndrome and organic lesions². According to Rome IV diagnostic criteria, the global incidence rate of FC is approximately 10.1%, with a higher incidence among individuals aged over 60 years^2,3. According to data, there are approximately 6 patients with FC for every 100 individuals in China. The prevalence of FC is 15.2% in urban women and 10.4% in rural women, and its prevalence in women is 8%, compared with 4% in men. In addition to inducing rectal cancer, FC can also cause cardiovascular events in the elderly⁴. Functional constipation is a multifactorial disease mainly related to heredity, lifestyle, colonic motility, rectal emptying disorders, psychosocial factors, and some drugs (e.g., anticholinergic and psychotropic drugs)⁵.

Western medicine often adopts Kai Sai Lu, laxatives, and other methods of relief for the treatment of constipation. However, long-term use of these interventions may lead to dependence and aggravate patients' anxiety and depression. Traditional Chinese medicine (TCM) has unique advantages in the treatment of chronic constipation. Acupoint application, a common treatment method in TCM, fully embodies the concept of external treatment of internal diseases. Plant medicine ground into powder, combined with a medium and applied to acupoints, stimulates these acupoints, producing drug effects for the treatment of disease⁶. In this study, Bawei Chengqi powder - a self-made prescription by Nantong-famous Chinese medicine doctor Zhang Baoliang - was used, mixed with honey. The prescription ratio was 150 g of peony; 100 g each of rhubarb, Magnolia officinalis, mirabilite, hemp seed, and Citrus aurantium; 60 g of almond; and 30 g of liquorice. The powder was applied to the Shenque (CV8) acupoint to treat elderly patients with FC. The results of a previous study show a significant increase in the frequency of defecation and a significant shortening in the interval between two stools after treatment⁷.

Music therapy has a 75 year history in European and American countries as a widely applied interdisciplinary technique and has been developed for nearly 22 years in China and used in clinical practice⁸. When an external music source with a rhythm coinciding with the micro-vibration of the human body flows through the auditory nerve to act on the body, the two produce a resonance phenomenon that can achieve an effect similar to a physical massage⁹. Music can also increase the endorphin content of blood (thereby reducing pain), regulate the heart rate and the release of certain hormones, and improve mood¹⁰. Five-tone therapy is a characteristic and classical treatment method in TCM¹¹. After its introduction to China, Western music therapy was combined with traditional music therapy to develop a modern five-tone therapy. Among these five tones, Gongdiao music (based on the Gong note [1-Do]) is characterized by its deep and melodious qualities, making it particularly suitable for patients with FC who also experience anxiety and depression. Research indicates that anxiety and depression not only serve as risk factors for FC but can also form a vicious cycle with gastrointestinal (GI) symptoms¹². In previous studies, this research group verified that five-tone therapy combined with acupoint application could relieve the negative emotions and improve the sleep quality and quality of life of patients with chronic hepatitis B with depression and spleen deficiency^13,14.

The midnight-noon ebb-flow theory (Zi Wu Liu Zhu) is a fundamental concept in TCM that correlates the 12 two-hour periods of the day with the cyclical flow of qi and blood through the 12 zang-fu organs and their corresponding meridians. It describes the temporal rhythm of human energy circulation, aligning with the modern concept of the biological clock¹⁵. By integrating this theory with five-tone therapy, treatment timing can be synchronized with the natural fluctuations of yin, yang, qi, and blood. Each musical five-tone is selected based on its correspondence to the wu xing (five elements) and zang-fu organs. For instance, in this study, Jue-tone music (Wood element), which enters the liver meridian, was primarily used to address liver stagnation and qi stagnation syndrome. Its melodies, reminiscent of the vitality of spring, are believed to soothe the liver and resolve stagnation. During the Chen hour (7:00-9:00, when the stomach meridian is dominant) and the Si hour (9:00-11:00, when the spleen meridian is dominant), a period corresponding to the peak flow of qi and blood in these Earth element-associated organs, Gong-tone music (such as soothing adaptations of "Ambush from Ten Sides") was selected to strengthen the spleen and stomach. This approach supports the source of qi and blood production, indirectly aiding the primary treatment goal through the principle of reinforcing the Earth to nourish the Wood. Such temporal alignment ensures that interventions are applied when the corresponding meridians are at their peak functional state, thereby enhancing therapeutic efficacy. During the mao hour (5:00-7:00), qi and blood are at their peak flow in the large intestine meridian of Hand Yangming. This period marks the optimal window for defecation, as the large intestine's transporting function is most active. In this study, acupoint application at the Shenque acupoint was specifically administered during this time to leverage the abundant qi and blood in the meridian, facilitating the direct transmission of herbal effects to the fu organs through meridian conduction. Establishing regular bowel habits during the mao hour helps maintain intestinal health and prevent functional disorders such as constipation, diarrhea, and abdominal pain.

This study primarily targeted adult patients with chronic FC (a duration of > 6 months) who had shown an inadequate response to conventional laxative therapies. Key practical considerations included a requirement for dedicated time slots (5:00-7:00) for five-tone therapy sessions and the availability of TCM preparation facilities. Important safety precautions included screening for abdominal skin integrity prior to acupoint application and monitoring for potential GI reactions during initial treatment phases. The combined five-tone therapy-acupoint application therapy demonstrated particular suitability for patients with constipation presenting with concurrent anxiety/depression symptoms, although it is contraindicated in pregnancy and specific TCM syndrome types. It also demonstrated superior efficacy over standard care in simultaneously improving GI symptoms (as evidenced by Bristol Stool Scale [BSFS] scores and defecation frequency) and psychological distress (as measured by the Patient Assessment of Constipation Symptoms scale [PAC-SYM] and Patient Assessment of Constipation Quality of Life scale [PAC-QOL] scores), thus achieving synergistic effects through dual-pathway regulation.

Protocol

The study protocol was approved by the Institutional Review Board of the Hai'an Hospital of Traditional Chinese Medicine (Approval no.: HZYLL2024042). Written informed consent was obtained from all participants prior to enrolment.

1. Patient screening and grouping

1. Use the convenience sampling method to enroll 103 patients with FC treated in the hospital between 1 June 2024 and 1 December 2024. Based on sequential enrolment numbers, divide participants into a study group and a control group according to their order of enrolment, with odd-numbered patients assigned to the study group (n = 52) and even-numbered patients assigned to the control group (n = 51).
2. For this study, include participants diagnosed with constipation and a qi stagnation pattern, as defined by the diagnostic criteria established in the Expert Consensus on TCM Diagnosis and Treatment of Constipation (2017) issued by the Spleen and Stomach Disease Branch of the China Association of Chinese Medicine¹⁶. Use the following diagnostic criteria:
   Main symptoms: dry and hard stool, reduced frequency of defecation, abdominal distension and pain, sensation of incomplete evacuation or difficulty in defecation.
   Secondary symptoms: borborygmus or frequent flatus, fullness and discomfort in the chest and hypochondrium, belching, emotional irritability or depression; dark red tongue with thin white coating, wiry pulse.
   A confirmed diagnosis requires the presence of all main symptoms, along with at least one secondary symptom, supported by corresponding tongue and pulse presentations.
3. Inclusion criteria: Include patients who met Rome IV diagnostic criteria for FC, aged 18-75 years, who provided their signed informed consent, and have at least a junior high school education, who could cooperate with the study.
4. Exclusion criteria: Exclude patients with secondary constipation (e.g., constipation due to intestinal obstruction or metabolic diseases); severe cardiac, hepatic, or renal dysfunction; pregnant or lactating women; patients with psychiatric disorders or using psychotropic medications; patients who had recently undergone surgery (within 1 month); and patients with an allergy to any of the study drug components. Eliminate patients if they fail to complete the treatment protocol, use other laxatives during the study, and/or lose to follow-up or voluntary withdrawal.
5. Verification of diagnostic criteria: Confirm all patients have met Rome IV criteria; that is, all patients exhibited a symptom duration >6 months and experienced two or more of the following symptoms with a frequency >25% in the last 3 months: (1) straining during defecation, (2) stool of BSFS classification type 1-2 (hard or lumpy stool), (3) a sensation of incomplete evacuation, (4) a sensation of anorectal obstruction, (5) manual maneuvers to facilitate defecation and (6) <3 spontaneous bowel movements per week.

2. Treatment procedure

1. Control group therapy
   1. For patients in the control group, maintain a fixed defecation time (within 30 min after waking) and ask them to follow a daily regimen, drinking 1,500-2,000 mL of water (measured with a graduated cup), consuming 25-30 g of dietary fiber (with reference to a fiber content chart) and performing 30 min of moderate-intensity exercise (target heart rate = [220 - age] x 60%). Give them 20 g (two 10 g sachets) of polyethylene glycol 4000 powder dissolved in 250 mL of warm water orally once each morning (6:00-7:00). Record time to first defecation and stool consistency (according to the BSFS). Discontinue medication if a patient experiences >3 bowel movements per day or watery stools.
2. Study group combination intervention
   1. For the study group, provide a combined intervention of five-tone therapy with Shenque acupoint application, in addition to conventional treatment.
   2. Five-tone therapy: Make patients listen to music daily (5:00-7:00) for 30 min per session and 7 days per course for 3 weeks. Eliminate distractions, and guide patients to calm their minds and relax their bodies. Ensure patients maintain focus while listening in a comfortable supine position at a volume of 30-40 dB.
      NOTE: The pieces of Gong-tone music selected for the study were Ambush from Ten Sides, Moonlight over the Spring River, and The Moon Represents My Heart. A radio with a memory card was used for music playback. The music playback equipment utilized the Sony CAS-1 High-Resolution Audio System. This device played lossless audio files in a unified format (FLAC 44.1 kHz/16-bit) via its built-in memory card. Prior to each use, the audio system underwent a self-check to ensure proper left/right channel balance and frequency response.
   3. Acupoint drug preparation: To prepare the study drug for application, combine white peony root (150 g), rhubarb (100 g), M. officinalis (100 g), immature bitter orange (100 g), mirabilite (100 g), hemp seed (100 g), almond (60 g) and liquorice (30 g) and ground using a TCM grinder at 28,000 rpm for three 2 min cycles. Mix the resultant powder with honey (with a moisture level of ≤ 20%) at a 1:2 ratio to form a paste. Store the mixture in sealed containers at 4 °C for ≤ 7 days.
   4. Safety monitoring: Inspect participants' skin for breaks or rashes within 5 cm of the Shenque acupoint and apply 5.0 ± 0.1 g of paste (weighed with an electronic balance). Secure with 8 x 8 cm hypoallergenic tape in a cross pattern. Maintain the application for 6 h (timed) for 3 consecutive weeks. Check participants' skin for reactions (e.g., erythema, itching) every 2 h and remove the paste immediately if any significant irritation occurs. Dispose of the used paste and dressings as medical waste. The combined therapy is illustrated in Figure 1.

3. Data collection

1. Collect general information (e.g., gender, age, body mass index [BMI], and course of disease), efficacy indicators, and safety data during treatment. Obtain efficacy indicators, including time to first defecation after treatment, PAC-SYM scores before and after treatment, and PAC-QOL scores before and after treatment.
2. Assess the reliability and validity of the scales. The Patient Assessment of Constipation Symptoms (PAC-SYM) scale demonstrated an internal consistency reliability with Cronbach's α coefficients ranging from 0.81 to 0.91, a test-retest reliability with intraclass correlation coefficients (ICC) ranging from 0.79 to 0.91, and a content validity index (CVI) of 0.82¹⁷. The Patient Assessment of Constipation Quality of Life (PAC-QOL) scale showed a Cronbach's α coefficient of 0.94 and a test-retest reliability of 0.80¹⁸.
3. Define time to first defecation after treatment as the time from treatment application to the first smooth defecation (accurate to the second decimal point). Constipation symptom scores referred to the 2017 Consensus on the Diagnosis and Treatment of Functional Constipation with Integrated Traditional Chinese and Western Medicine¹⁹ and constipation symptoms outlined in the Rome IV diagnostic criteria²⁰ (Table 1).
4. Define stool traits as referred to the BSFS²¹, where stool is classified as follows: type I, a nut-like hard ball; type II, sausage-like but with a convex surface; type III, sausage-like with surface cracks; type IV, sausage- or snake-like with a smooth surface; type V, a smooth, soft block with a broken edge; type VI, a paste-like, thick-edged fluffy block; and type VII, a watery sample (not solid). Give stools classified as type IV-VII a score of 0, type III 1 point, type II 2 points, and type I 3 points.

4. Patient assessment

1. Patient assessment of constipation quality of life scale
   1. For the Chinese version of the PAC-QOL scale, this study referred to the Mapi Research Trust's authorized development of a quality-of-life self-rating scale for patients with constipation²². Use the PAC-QOL scale to reflect the impact of constipation on patients' daily life in the previous 2 weeks and include a total of 28 items relating to four dimensions: (1) physical discomfort (items 1-4), which mainly reflect the physiological discomfort caused by constipation, such as abdominal distension, the feeling of a heavy body, intentional but not excluded and other physical discomfort; (2) psychosocial discomfort (items 5-12), which mainly reflect the impact of constipation on a patient's social life (i.e., self-image, interaction with others and comfort in a public environment); (3) worry and anxiety (items 13-23), which mainly reflect the emotional changes, such as worry, stress and tension, brought on by constipation; and (4) satisfaction (items 24-28), which mainly reflect a patient's degree of satisfaction with defecation frequency, regularity, function and treatment.
   2. Score each item using a 5-point method according to the degree of discomfort, with 0 = no discomfort, 1 = some discomfort, 2 = moderate discomfort, 3 = a lot of discomfort, and 4 = great discomfort (with items 24-28 scored in the reverse direction). Calculate the score of each dimension by taking the average of all items in that dimension and calculate the total score as the average score of all items. A higher score reflected more serious constipation and a lower quality of life.
2. Patient assessment of constipation symptoms scale
   1. The PAC-SYM used in this study was developed with reference to the 2005 edition of Constipation Symptoms and Efficacy Evaluation²³. Include the following six items: defecation duration, difficulty of defecation, anal bulge during defecation, defecation frequency, abdominal distension, and stool traits (according to BSFS stool trait map classification) in the assessment. Use a conventional four-level scoring method (0-3 points) and set the score interval to 0-18 points. A higher score correlated with more severe symptoms.

5. Statistical analysis

1. Perform statistical analysis using SPSS 26.0 statistical software. Perform a normality test using the Kolmogorov-Smirnov method. Express measurement data that satisfied normality as mean ± standard deviation. Use a paired design t-test to compare the mean between the two groups, and an independent sample t-test for group design.
2. Express data that did not follow a normal distribution as the median (Q1, Q3). Use the Mann-Whitney U test and the Kruskal-Wallis H rank sum test for comparisons between groups. Express count data as frequency (n) or rate (%). Use a chi-squared (χ²) test for data that met the conditions, and Fisher's exact probability method for data that did not meet the conditions. Consider a two-sided p-value < 0.05 statistically significant.

Results

During the trial, in strict accordance with implementation of the research protocol, one patient in the study group was eliminated due to a long absence and subsequent inability to complete the study, one patient in the study group was eliminated due to a local skin allergy, and one patient in the control group ceased participation for personal reasons. The number of treatments received by the 3 participants eliminated was less than half, and a total of 100 participants completed the trial.

There were 31 men and 19 women in the study group, with an average age of 53.48 ± 9.26 years and a course of disease of 8.46 ± 4.07 years. There were 25 men and 25 women in the control group, with an average age of 56.96 ± 8.46 years and a course of disease of 9.08 ± 4.12 years. There was no significant difference in gender, age, BMI, or course of disease between the two groups (p > 0.05), as shown in Table 2.

There was no significant difference in BSFS classification, defecation frequency, defecation time, defecation effort, incomplete defecation, abdominal distension, abdominal pain, or anal obstruction between the two groups before intervention (p > 0.05). After intervention, BSFS classification scores, defecation frequency, defecation effort, incomplete defecation, abdominal distension, and abdominal pain were lower in the study group than in the control group (p < 0.05). Compared with scores before intervention, BSFS classification, defecation frequency, defecation time, defecation difficulty, incomplete defecation, abdominal distension, abdominal pain, and anal obstruction in the study group were improved after intervention (p < 0.05). Defecation frequency, defecation difficulty, incomplete defecation, abdominal distension, and abdominal pain in the control group were also improved (p < 0.05), as shown in Table 3.

There was no significant difference in physical discomfort, psychosocial discomfort, worry, anxiety, or satisfaction scores between the two groups before the intervention (p > 0.05). After intervention, physical discomfort (0.88 ± 0.33 vs 1.20 ± 0.40, p < 0.001), psychosocial discomfort (1.02 ± 0.14 vs 1.46 ± 0.50, p < 0.001), worry and anxiety (1.02 ± 0.32 vs 1.56 ± 0.50, p < 0.001) and satisfaction (1.18 ± 0.39 vs 1.48 ± 0.50, p < 0.001) scores in the study group were lower than those in the control group. The physical discomfort, psychosocial discomfort, worry and anxiety, and satisfaction scores of the two groups decreased after intervention (p < 0.05), as shown in Figure 2 and Table 4.

There was no significant difference in PAC-SYM scores between the two groups before intervention (p > 0.05). After intervention, the PAC-SYM scores of the study group decreased (p < 0.05), and the mean PAC-SYM score of the study group was lower than that of the control group (14.64 ± 2.51 vs 18.70 ± 1.28, p < 0.001). The time to first defecation of the study group after intervention was better than that of the control group (0.85 ± 0.45 vs 1.68 ± 0.43, p < 0.001; see Figure 3 and Table 5).

There were two cases of adverse reactions in the study group during intervention, including one case of local erythema pruritus and one case of local erythema. There were four cases of adverse reactions in the control group, including one case of nausea and three cases of diarrhea. There was no significant difference in the incidence of adverse reactions between the two groups (p = 0.400; see Table 6). The degree of adverse reactions in patients was mild, and they all recovered well after treatment.

Figure 1: Schematic diagram of the treatment protocol. Please click here to view a larger version of this figure.

Figure 2: PAC-QOL score (A) Body discomfort, (B) Psychosocial discomfort, (C) Worry and anxiety, (D) Satisfaction. Mann-Whitney U test and the Kruskal-Wallis H rank sum test **p < 0.01, ****p < 0.0001; n =50. Data shows mean ± standard deviation. Please click here to view a larger version of this figure.

Figure 3: PAC-SYM score. The score is shown before and after the intervention for the two groups. Mann-Whitney U test and the Kruskal-Wallis H rank sum test ****p < 0.0001; n = 50. Data shows mean ± standard deviation. Please click here to view a larger version of this figure.

Table 1: Constipation symptom rating scale. Please click here to download this Table.

Table 2: General data comparison. Abbreviation: BMI = Body Mass Index. Please click here to download this Table.

Table 3: Comparison of constipation symptom scores before and after treatment. *: The difference was statistically significant compared with the before intervention. Please click here to download this Table.

Table 4: Comparison of PAC-QOL scores before and after intervention. *: The difference was statistically significant compared with the Before intervention; PAC-QOL: Patient Assessment of Constipation Quality of Life. Please click here to download this Table.

Table 5: Comparison of time to first defecation and PAC-SYM scores before and after intervention. *: The difference was statistically significant compared with the Before intervention; PAC-SYM: Patient Assessment of Constipation Symptoms Please click here to download this Table.

Table 6: Comparison of adverse reactions. Please click here to download this Table.

Discussion

Compared with conventional Western medicine, the combined therapy used in this study demonstrates superior efficacy, leads to greater improvements in core outcomes (specifically, BSFS scores and defecation frequency), and provides enhanced relief from accompanying symptoms (such as abdominal distension and incomplete evacuation). Five-tone therapy alleviates anxiety by regulating autonomic nervous function, creating a synergistic effect with the local pharmacological action of acupoint application. Furthermore, when compared with current acupoint application monotherapy for FC, the protocol demonstrates additional comprehensive advantages, including a lower incidence of adverse reactions, a more refined symptom assessment system, and higher overall symptom remission rates²⁴.

Functional constipation belongs to the constipation category of TCM. According to TCM^23,25, constipation is a disorder resulting from the abnormal conduction function of the large intestine and clinically manifests as dry stool, a reduced frequency of defecation, or frequent but poor defecation. According to modern TCM²⁶, the aetiology of constipation is mostly related to diet, emotion, old age, physical deficiency, and a feeling of external evils. Its basic pathogenesis is the loss of large intestine conduction. Although it is mainly located in the large intestine, the disease also involves lungs, spleen, stomach, liver, kidneys, and other organs. The nature of the disease follows two possible patterns: deficiency or excess. The excess syndrome has a heat pattern, qi pattern, and cold pattern, whereas the deficiency syndrome has a qi deficiency pattern, blood deficiency pattern, yang deficiency pattern, and yin deficiency pattern. Empirical treatment of the excess syndrome mainly involves eliminating pathogenic factors, whereas treatment of the deficiency syndrome involves strengthening the body.

The mechanism of acupoint application is two-fold, involving both the role of the applied drug and the role of the acupoints. The human meridian system belongs to the zang-fu organs, and external collaterals are in the limb joints, which can run qi and blood and communicate with the exterior and interior environments. An acupoint is a special part of the viscera and meridians of qi and blood infusion that lies outside the body²⁷. Drug applications are directly absorbed into the human body at acupoints and transmitted through the meridians of the five zang organs, six fu organs, and nine orifices of the limbs to exert their pharmacological effects. By stimulating acupoints at the application site, medication also promotes the flow of qi throughout the meridian system, thereby initiating the holistic regulation of the body's energetic pathways²⁸. Modern research suggests that, compared with the surrounding skin, acupoints exhibit characteristics such as low impedance, large capacitance, high-point electro-acupoint potential, and specific acoustic and thermal changes that make them more sensitive to external stimuli and capable of amplifying the effects of administered medications²⁹. Scholars also propose the hypothesis of the low-flow resistance channel of meridians and believe the effects of acupoint application can be achieved by dredging the low-flow resistance channel of the meridian³⁰. A drug acts on and stimulates an acupoint, producing specific thermal changes. Certain components can readily penetrate the skin, reach deep into acupoints, and travel along meridian pathways to disease sites or throughout the body³¹. Acupoint application belongs to the category of transdermal drug delivery in modern medicine. Drugs absorbed through this pathway rarely metabolize through the liver, avoiding the liver's first-pass effect, and do not pass through the digestive tract, leaving drug components free from GI inactivation without stimulating the GI tract³².

The main effects of eight-ingredient Bawei Chengqi powder are to purge accumulation, relieve stagnation in the fu organs, and clear heat. One study has noted that its essence is not only to dredge the lower fu organs but also to regulate qi movement²⁶. A modern pharmacological study has shown that the anthraquinones and their derivatives contained in rhubarb can excite the colon, enhance intestinal contractile activity, and promote intestinal peristalsis. Rhubarb also has antipyretic, cooling, anti-inflammatory, antibacterial and other pharmacological effects³³. The main component of mirabilite is sodium sulphate. After dissolution, the sulphate ions of sodium sulphate form a hypertonic salt solution in the intestine that absorbs a considerable amount of water, thereby expanding the intestinal lumen. This triggers mechanical stimulation and thus promotes intestinal peristalsis³⁴. Fructus aurantii immaturus has been shown to stimulate GI smooth muscle, enhance gastric motility, accelerate gastric emptying, and improve digestion and absorption in the small intestine³⁵. Houpo magnolia can enhance intestinal propulsion rates and inhibit hydrochloric acid damage to gastric ulcers³⁶.

At present, research on the mechanism of five-tone therapy in the treatment of FC is lacking. In this study, we speculate that the mechanism of five-tone therapy is as follows: first, listening to music can increase dopamine release in listeners, resulting in pleasant emotions; second, music can reduce the serum cortisol concentration of anxious individuals, thus alleviating anxiety; and third, music can enhance the body's immunity and improve patients' pain tolerance after surgery, contributing to postoperative recovery and wound healing. Other studies have shown that when appropriate music rhythm resonates with human cells, coordination between tissues and organs can be gradually restored, thereby promoting the body's recovery.

The successful implementation of this protocol relies on three key elements: strict adherence to the mao hour (5:00-7:00) to align with the large intestine meridian's peak energy flow; precise selection of the Shenque acupoint, leveraging its thin and permeable skin for optimal drug absorption; and standardized parameters, including Gong-tone music at 30-40 dB and Bawei Chengqi powder mixed with honey at a 1:2 ratio, ensuring reproducibility.

Practical refinements include adjusting the honey ratio to 1:1.8 and pre-cleaning the periumbilical area to address poor paste adhesion, substituting softer melodies such as Colorful Clouds Chasing the Moon, and implementing volume gradation for music intolerance, shortening application times for skin allergies, and using WeChat reminders with a flexible ± 15 min window to address low compliance.

This therapy holds broad application potential. Simplified acupoint kits paired with mobile app guidance can enable home-based management, the therapy can prevent opioid-induced constipation in post-colorectal surgery patients, and modified formulations may extend to early intervention for diabetic GI complications.

The limitations of this study include the single-center nature of its sample and its lack of double-blinding. Future multi-center randomized controlled trials incorporating functional magnetic resonance imaging may elucidate the mechanism of five-tone therapy on the brain-gut axis, and standardized preparations may enhance clinical utility.

In conclusion, this spatiotemporally targeted combination therapy, aligning timing, acupoint application, and other parameters, offers an effective TCM-based solution to FC, with a modular design that supports broader adoption and adaptation.

Materials

List of materials used in this article

Name	Company	Catalog Number	Comments
polyethylene glycol 4000 powder	Bofu-Ipsen	No. H20171247