This is a good article. Click here for more information.

Rumination syndrome

From WikiProjectMed
Jump to navigation Jump to search
Rumination syndrome
Other names: Merycism
A line graph. The line has pronounced upwards spikes followed by less pronounced downward spikes. These spikes are separated by longer intermittent periods where the line is jagged, but roughly and statistically straight.
A pressure measurement after eating in a person with rumination syndrome showing intra-abdominal pressure "spikes". These represent abdominal wall contractions responsible for the regurgitation.
SymptomsRegurgitation of most meals following eating[1]
ComplicationsMalnutrition, weight loss, electrolyte problems, enamel breakdown, bad breath[1]
Diagnostic methodBased on symptoms; esophageal motility study[1]
Differential diagnosisGERD, achalasia, gastroparesis, bulimia, gastric outlet obstruction[1]
TreatmentReassurance, biofeedback, diaphragmatic breathing[1]
Frequency0.8% of people[2]

Rumination syndrome is a disorder characterized by effortless regurgitation of most meals following eating.[1] There is generally no retching, little nausea, and the food is undigested.[1] There may be some abdominal discomfort immediately following eating.[1] The condition is long-term in nature.[1] Complications may include malnutrition, weight loss, electrolyte problems, enamel breakdown, and bad breath.[1]

The cause is unknown.[2] The condition may begin following a trigger such as psychological stress or gastroenteritis.[1] The underlying mechanism involves subconscious contraction of the muscles around the abdomen together with relaxation of the lower esophageal sphincter.[1] Diagnosis is generally based on symptoms after ruling out other potential causes; an esophageal motility study may be used in unclear cases.[1][3] Other conditions that may appear similar include GERD, achalasia, gastroparesis, and bulimia.[1]

Treatment is effective in most people.[1] Measures generally include biofeedback and diaphragmatic breathing.[1] Patient education and reassurance are also important.[1] Other measures may include baclofen or Nissen's fundoplication, but these are less preferred.[1] Nasogastric tube feeding may be required in those who are malnourished.[1]

Rumination syndrome is uncommon, affecting about 0.8% of people.[2][4] Of those with fibromyalgia or an eating disorder, 10% may be affected.[2] Among children, females are more commonly affected than males.[1][2] The condition was first described in 1618 in people.[1]

Signs and symptoms

While the number and severity of symptoms vary among individuals, repetitive regurgitation of undigested food (known as rumination) after the start of a meal is always present.[5][6] In some individuals, the regurgitation is small, occurring over a long period of time following ingestion, and can be rechewed and swallowed. In others, the amount can be bilious and short-lasting, and must be expelled. While some only experience symptoms following some meals, most experience episodes following any ingestion, from a single bite to a large meal.[7] However, some long-term patients will find a select couple of food or drink items that do not trigger a response.

Unlike typical vomiting, regurgitation is typically described as effortless and unforced.[5] There is seldom nausea preceding the expulsion, and the undigested food lacks the bitter taste and odour of stomach acid and bile.[5]

Symptoms can begin to manifest at any point from the ingestion of the meal to two hours thereafter.[6] However, the more common range is between thirty seconds and one hour after the completion of a meal.[7] Symptoms tend to cease when the ruminated contents become acidic.[5][7]

Abdominal pain (38%), lack of fecal production or constipation (21%), nausea (17%), diarrhea (8%), bloating (4%), and dental decay (3%) are also described as common symptoms in day-to-day life.[6] These symptoms are not necessarily present during regurgitation episodes, and can happen at any time. Weight loss is often observed (42%) at an average loss of 9.6 kilograms, and is more common in cases where the disorder has gone undiagnosed for a longer period of time,[6] though this may be expected of the nutrition deficiencies that often accompany the disorder as a consequence of its symptoms.[6] Depression has also been linked with rumination syndrome,[8] though its effects on rumination syndrome are unknown.[5]

Acid erosion of the teeth can be a feature of rumination,[9] as can bad breath.[10]


The cause of rumination syndrome is unknown. However, studies have drawn a correlation between hypothesized causes and the history of patients with the disorder. In infants and the cognitively impaired, the disease has normally been attributed to overstimulation and under-stimulation from parents and caregivers, causing the individual to seek self-gratification and self-stimulus due to the lack or abundance of external stimuli. The disorder has also commonly been attributed to a bout of illness, a period of stress in the individual's recent past, and to changes in medication.[5]

In adults and adolescents, hypothesized causes generally fall into one of either category: habit-induced, and trauma-induced. Habit-induced individuals generally have a history of bulimia nervosa or of intentional regurgitation (magicians and professional regurgitators, for example), which though initially self-induced, forms a subconscious habit that can continue to manifest itself outside the control of the affected individual. Trauma-induced individuals describe an emotional or physical injury (such as recent surgery, psychological distress, concussions, deaths in the family, etc.), which preceded the onset of rumination, often by several months.[5][6]


Rumination syndrome is a poorly understood disorder, and a number of theories have speculated the mechanisms that cause the regurgitation,[6] which is a unique symptom to this disorder. While no theory has gained a consensus, some are more notable and widely published than others.[5]

The most widely documented mechanism is that the ingestion of food causes gastric distention, which is followed by abdominal compression and the simultaneous relaxation of the lower esophageal sphincter (LES). This creates a common cavity between the stomach and the oropharynx that allows the partially digested material to return to the mouth. There are several offered explanations for the sudden relaxation of the LES.[11] Among these explanations is that it is a learned voluntary relaxation, which is common in those with or having had bulimia. While this relaxation may be voluntary, the overall process of rumination is still generally involuntary. Relaxation due to intra-abdominal pressure is another proposed explanation, which would make abdominal compression the primary mechanism. The third is an adaptation of the belch reflex, which is the most commonly described mechanism. The swallowing of air immediately prior to regurgitation causes the activation of the belching reflex that triggers the relaxation of the LES. Patients often describe a feeling similar to the onset of a belch preceding rumination.[5]


Rumination syndrome is diagnosed based on a complete history of the individual. Studies such as gastroduodenal manometry and esophageal pH testing are not usually necessary and may result in misdiagnosis.[5] Based on typical observed features, several criteria have been suggested for diagnosing rumination syndrome.[6] The primary symptom, the regurgitation of recently ingested food, must be consistent, occurring for at least six weeks of the past twelve months. The regurgitation must begin within 30 minutes of the completion of a meal. People may either chew the regurgitated matter or expel it. The symptoms must stop within 90 minutes, or when the regurgitated matter becomes acidic. The symptoms must not be the result of a mechanical obstruction, and should not respond to the standard treatment for gastroesophageal reflux disease.[5]

In adults, the diagnosis is supported by the absence of classical or structural diseases of the gastrointestinal system. Supportive criteria include a regurgitant that does not taste sour or acidic,[11] is generally odourless, is effortless,[7] or at most preceded by a belching sensation,[5] that there is no retching preceding the regurgitation,[5] and that the act is not associated with nausea or heartburn.[5]

People frequently have a delayed diagnosis or are inappropriately diagnosed with another condition.[12]


Rumination syndrome is a condition which affects the functioning of the stomach and esophagus, also known as a functional gastroduodenal disorder.[13] In people that have a history of eating disorders, Rumination syndrome is grouped alongside eating disorders such as bulimia and pica, which are themselves grouped under non-psychotic mental disorder. In most healthy adolescents and adults who have no mental disability, Rumination syndrome is considered a motility disorder instead of an eating disorder, because the patients tend to have had no control over its occurrence and have had no history of eating disorders.[14][15]

Differential diagnosis

Rumination syndrome in adults is a complicated disorder whose symptoms can mimic those of several other gastroesophageal disorders and diseases. Bulimia and gastroparesis are especially common among the misdiagnoses of rumination.[5]

Bulimia, among adults and especially adolescents, is by far the most common misdiagnosis patients will hear during their experiences with rumination syndrome. This is due to the similarities in symptoms to an outside observer—"vomiting" following food intake—which, in long-term patients, may include ingesting copious amounts to offset malnutrition, and a lack of willingness to expose their condition and its symptoms. While it has been suggested that there is a connection between rumination and bulimia,[16][17] unlike bulimia, rumination is not self-inflicted. Adults and adolescents with rumination syndrome are generally well aware of their gradually increasing malnutrition, but are unable to control the reflex. In contrast, those with bulimia intentionally induce vomiting, and seldom re-swallow food.[5]

Gastroparesis is another common misdiagnosis.[5] Like rumination syndrome, patients with gastroparesis often bring up food following the ingestion of a meal. Unlike rumination, gastroparesis causes vomiting (in contrast to regurgitation) of food, which is not being digested further, from the stomach. This vomiting occurs several hours after a meal is ingested, preceded by nausea and retching, and has the bitter or sour taste typical of vomit.[7]

Treatment and prognosis

In people of normal intelligence, rumination is not an intentional behavior and is habitually reversed using diaphragmatic breathing to counter the urge to regurgitate.[18] Alongside reassurance, explanation and habit reversal, people are shown how to breathe using their diaphragms prior to and during the rumination period.[18][19] A similar breathing pattern can be used to prevent normal vomiting. Breathing in this method works by physically preventing the abdominal contractions required to expel stomach contents.

Supportive therapy and diaphragmatic breathing has shown to improve 56% of cases, and total cessation of symptoms in an additional 30% in one study of 54 adolescents who were followed up 10 months after initial treatments.[6] People who successfully use the technique often notice an immediate change in health for the better.[18] Individuals who have had bulimia or who intentionally induced vomiting in the past have a reduced chance for improvement due to the reinforced behavior.[16][18] The technique is not used with infants or young children due to the complex timing and concentration required. Most infants grow out of the disorder within a year or with aversive training.[20]

If other measures are not effective baclofen 10 mg three times per day may be used.[4] Proton pump inhibitors are of little to no effect.[18]

Developmental disability

Treatment is different for infants and mentally disabled adults than otherwise normal adults and adolescents. Among infants and mentally disabled adults, behavioral and mild aversion training has been shown to improve most cases.[21] Aversion training involves associating the ruminating behavior with negative results, and rewarding good behavior and eating. Placing a sour or bitter taste on the tongue when the individual begins the movements or breathing patterns typical of their ruminating behavior is the generally accepted method for aversion training,[21] although some older studies advocate the use of pinching.[citation needed]


A chart visualizing the distribution of patients (by age) at the diagnosis of rumination syndrome. It is a bar graph, representing ages between newborn and 20. No patients under 5 were used. The graph peaks in the 14 to 18 years range, with the most patients being diagnosed at 17 (20 of the 145 patients). Moving away from 17 years of age, the number of patients diagnosed tapers off gradually.
Age distribution at diagnosis[6]

Rumination disorder was initially documented[20][22] as affecting newborns,[15] infants, children[14] and individuals with mental and functional disabilities (cognitively disabled).[22][23] It has since been recognized to occur in both males and females of all ages and cognitive abilities.[5][24]

Among cognitively disabled people, it is described with almost equal prevalence among infants (6–10% of the population) and institutionalized adults (8–10%).[5] In infants, it typically occurs within the first 3–12 months of age.[20]

The occurrence of rumination syndrome within the general population has not been defined.[13] Rumination is sometimes described as rare,[5] but has also been described as not rare, but rather rarely recognized.[25] The disorder has a female predominance in children.[13] The average age of onset is 13, with males affected sooner than females (11 for males versus 14 for females).[6]

There is little evidence of hereditary influence in rumination syndrome.[11] However, case reports involving entire families exist.[26]


The term "rumination" is derived from the Latin word "ruminare", which means "to chew the cud".[26] First described in ancient times, and mentioned in the writings of Aristotle, rumination syndrome was clinically documented in 1618 by Italian anatomist Fabricus ab Aquapendente, who wrote of the symptoms in a patient of his.[24][26]

Among the earliest cases of rumination was that of a physician in the nineteenth century, Charles-Édouard Brown-Séquard, who acquired the condition as the result of experiments upon himself. As a way of evaluating and testing the acid response of the stomach to various foods, the doctor would swallow sponges tied to a string, then intentionally regurgitate them to analyze the contents. As a result of these experiments, the doctor eventually regurgitated his meals habitually by reflex.[27]

Numerous case reports exist from before the twentieth century, but were influenced greatly by the methods and thinking used in that time. By the early twentieth century, it was becoming increasingly evident that rumination presented itself in a variety of ways in response to a variety of conditions.[24] Although still considered a disorder of infancy and cognitive disability at that time, the difference in presentation between infants and adults was well established.[26]

Studies of rumination in otherwise healthy adults became decreasingly rare starting in the 1900s, and the majority of published reports analyzing the syndrome in mentally healthy patients appeared thereafter. At first, adult rumination was described and treated as a benign condition. It is now described as otherwise.[28] While the base of patients to examine has gradually increased as more and more people come forward with their symptoms, awareness of the condition by the medical community and the general public is still limited.[5][25][29][30]

Other animals

The chewing of cud by animals such as cows, goats, and giraffes is considered normal behavior. These animals are known as ruminants.[11] Such behavior, though termed rumination, is not related to human rumination syndrome, but is ordinary. Involuntary rumination, similar to what is seen in humans, has been described in gorillas and other primates.[31] Macropods such as kangaroos also regurgitate, re-masticate, and re-swallow food, but these behaviors are not essential to their normal digestive process, are not observed as predictably as the ruminants', and hence were termed "merycism" in contrast with "true rumination".[32]

See also


  1. 1.00 1.01 1.02 1.03 1.04 1.05 1.06 1.07 1.08 1.09 1.10 1.11 1.12 1.13 1.14 1.15 1.16 1.17 1.18 1.19 1.20 1.21 Sasegbon, Ayodele; Hasan, Syed Shariq; Disney, Benjamin R; Vasant, Dipesh Harshvadan (September 2022). "Rumination syndrome: pathophysiology, diagnosis and practical management". Frontline Gastroenterology. 13 (5): 440–446. doi:10.1136/flgastro-2021-101856. PMID 36046491.
  2. 2.0 2.1 2.2 2.3 2.4 2.5 "Rumination Syndrome". Guts UK. Archived from the original on 29 May 2023. Retrieved 25 June 2023.
  3. Alcala-Gonzalez, LG; Serra, X; Barba, E (February 2022). "Rumination syndrome: Critical review". Gastroenterologia y hepatologia. 45 (2): 155–163. doi:10.1016/j.gastrohep.2021.03.013. PMID 34023479.
  4. 4.0 4.1 Halland, M; Pandolfino, J; Barba, E (October 2018). "Diagnosis and Treatment of Rumination Syndrome". Clinical gastroenterology and hepatology : the official clinical practice journal of the American Gastroenterological Association. 16 (10): 1549–1555. doi:10.1016/j.cgh.2018.05.049. PMID 29902642.
  5. 5.00 5.01 5.02 5.03 5.04 5.05 5.06 5.07 5.08 5.09 5.10 5.11 5.12 5.13 5.14 5.15 5.16 5.17 5.18 5.19 5.20 Papadopoulos, Vassilios; Mimidis, Konstantinos (July–September 2007), "The rumination syndrome in adults: A review of the pathophysiology, diagnosis and treatment", Journal of Postgraduate Medicine, 53 (3): 203–206, doi:10.4103/0022-3859.33868, PMID 17699999
  6. 6.00 6.01 6.02 6.03 6.04 6.05 6.06 6.07 6.08 6.09 6.10 Chial, Heather J; Camilleri, Michael; Williams, Donald E; Litzinger, Kristi; Perrault, Jean (2003), "Rumination syndrome in children and adolescents: diagnosis, treatment, and prognosis", Pediatrics, 111 (1): 158–162, doi:10.1542/peds.111.1.158, PMID 12509570, archived from the original on 2010-06-25, retrieved 2023-03-29
  7. 7.0 7.1 7.2 7.3 7.4 Camilleri, Michael; Seime, Richard J, Rumination Syndrome, symptoms, Rochester, Minnesota: Mayo Clinic, archived from the original on 2009-07-25, retrieved 2009-06-26
  8. Amarnath RP, Abell TL, Malagelada JR (October 1986), "The rumination syndrome in adults. A characteristic manometric pattern.", Annals of Internal Medicine, 105 (4): 513–518, doi:10.7326/0003-4819-105-4-513, PMID 3752757
  9. Adrian Lussi (2006). Dental erosion from diagnosis to therapy; 22 tables. Basel: Karger. p. 120. ISBN 9783805580977. Archived from the original on 2023-07-02. Retrieved 2023-03-29.
  10. Carey WB, Crocker AC, Coleman WL, Feldman HM, Elias ER (2009). Developmental-behavioral pediatrics (4th ed.). Philadelphia, PA: Saunders/Elsevier. p. 634. ISBN 9781416033707. Archived from the original on 2023-07-02. Retrieved 2023-03-29.
  11. 11.0 11.1 11.2 11.3 Ellis, Cynthia R; Schnoes, Connie J (2009), "Eating Disorder, Rumination", Medscape Pediatrics, archived from the original on 2009-07-21, retrieved 2009-09-07
  12. Murray, HB; Juarascio, AS; Di Lorenzo, C; Drossman, DA; Thomas, JJ (April 2019). "Diagnosis and Treatment of Rumination Syndrome: A Critical Review". The American journal of gastroenterology. 114 (4): 562–578. doi:10.14309/ajg.0000000000000060. PMID 30789419.
  13. 13.0 13.1 13.2 Tack, Jan; Talley, Nicholas J; Camilleri, Michael; Holtmann, Gerald; Hu, Pinjin; Malagelada, Juan-R; Stanghellini, Vincenzo (2006), "Functional gastroduodenal disorders" (PDF), Gastroenterology, 130 (5): 1466–1479, doi:10.1053/j.gastro.2005.11.059, PMID 16678560, archived (PDF) from the original on 2020-11-25, retrieved 2023-03-29
  14. 14.0 14.1 ICD-10 entries for rumination syndrome - F98.2, archived from the original on 2009-08-12, retrieved 2009-08-10
  15. 15.0 15.1 ICD-10 entries for rumination syndrome - P92.1, archived from the original on 2009-08-12, retrieved 2009-08-10
  16. 16.0 16.1 LaRocca, Felix E; Della-Fera, Mary-Anne (October 1986), "Rumination: Its significance in adults with bulimia nervosa", Psychosomatics, 27 (3): 209–212, doi:10.1016/s0033-3182(86)72713-8, PMID 3457391
  17. O'Brien, Michael D; Bruce, Barbara K; Camilleri, Michael (March 1995), "The rumination syndrome: Clinical features rather than manometric diagnosis", Gastroenterology, 108 (4): 1024–1029, doi:10.1016/0016-5085(95)90199-X, PMID 7698568
  18. 18.0 18.1 18.2 18.3 18.4 Chitkara, Denesh K; van Tilburg, Miranda; Whitehead, William E; Talley, Nicholas (2006), "Teaching diaphragmatic breathing for rumination syndrome", The American Journal of Gastroenterology, 101 (11): 2449–2452, doi:10.1111/j.1572-0241.2006.00801.x, PMID 17090274, S2CID 25492775, archived from the original on 2023-07-02, retrieved 2023-03-29
  19. Johnson, WG; Corrigan, SA; Crusco, AH; Jarell, MP (1987), "Behavioral assessment and treatment of postprandial regurgitation", Journal of Clinical Gastroenterology, 9 (6): 679–684, doi:10.1097/00004836-198712000-00013, PMID 3443732
  20. 20.0 20.1 20.2 Rasquin-Weber, A; Hyman, PE; Cucchiara, S; Fleisher, DR; Hyams, JS; Milla, PJ; Staiano, A (1999), "Childhood functional gastrointestinal disorders", Gut, 45 (Supplement 2) (Suppl 2): 1160–1168, doi:10.1136/gut.45.2008.ii60, PMC 1766693, PMID 10457047
  21. 21.0 21.1 Wagaman, JR; Williams, DE; Camilleri, M (1998), "Behavioral intervention for the treatment of rumination", Pediatric Gastroenterology and Nutrition, 27 (5): 596–598, doi:10.1097/00005176-199811000-00019, PMID 9822330
  22. 22.0 22.1 Sullivan, PB (1997), "Gastrointestinal problems in the neurologically impaired child", Baillière's Clinical Gastroenterology, 11 (3): 529–546, doi:10.1016/S0950-3528(97)90030-0, PMID 9448914
  23. Rogers, B; Stratton, P; Victor, J; Cennedy, B; Andres, M (1992), "Chronic regurgitation among persons with mental retardation: A need for combined medical and interdisciplinary strategies", American Journal of Mental Retardation, 96 (5): 522–527, PMID 1562309
  24. 24.0 24.1 24.2 Olden, Kevin W (2001), "Rumination", Current Treatment Options in Gastroenterology, 4 (4): 351–358, doi:10.1007/s11938-001-0061-z, PMID 11469994, archived from the original on February 15, 2012
  25. 25.0 25.1 Fox, Mark; Young, Alasdair; Anggiansah, Roy; Anggiansah, Angela; Sanderson, Jeremy (2006), "A 22 year old man with persistent regurgitation and vomiting: case outcome", British Medical Journal, 333 (7559): 133, discussion 134–7, doi:10.1136/bmj.333.7559.133, PMC 1502216, PMID 16840471, archived from the original on 2017-04-01, retrieved 2023-03-29
  26. 26.0 26.1 26.2 26.3 Brockbank, EM (1907), "Merycism or Rumination in Man", British Medical Journal, 1 (2408): 421–427, doi:10.1136/bmj.1.2408.421, PMC 2356806, PMID 20763087
  27. Kanner, L (February 1936), "Historical notes on rumination in man", Medical Life, 43 (2): 27–60, OCLC 11295688
  28. Sidhu, Shawn S; Rick, James R (2009), "Erosive eosinophilic esophagitis in rumination syndrome", Jefferson Journal of Psychiatry, 22 (1), doi:10.29046/JJP.022.1.002, ISSN 1935-0783, archived from the original on 2016-03-03, retrieved 2023-03-29
  29. Camilleri, Michael; Seime, Richard J, Rumination Syndrome, an overview, Rochester, Minnesota: Mayo Clinic, archived from the original on 2009-05-15, retrieved 2009-06-26
  30. Parry-Jones, B (1994), "Merycism or rumination disorder. A historical investigation and current assessment", British Journal of Psychiatry, 165 (3): 303–314, doi:10.1192/bjp.165.3.303, PMID 7994499, S2CID 25471168
  31. Hill, SP (May 2009), "Do gorillas regurgitate potentially-injurious stomach acid during 'regurgitation and reingestion?'", Animal Welfare, 18 (2): 123–127, doi:10.1017/S0962728600000269, ISSN 0962-7286, S2CID 53832798, archived from the original on 2023-07-02, retrieved 2023-03-29
  32. Vendl, C. et al. (2017). "Merycism in western grey (Macropus fuliginosus) and red kangaroos (Macropus rufus)". Mammalian Biology. 86: 21–26. doi:10.1016/j.mambio.2017.03.005.{{cite journal}}: CS1 maint: uses authors parameter (link)

External links

External resources