Summary of the main foregut gut–brain disorders, key features, management options and optimal nutrition approach
| Foregut gut–brain disorder diagnosis | Key features | Diagnostic basis and tests | Management options | Optimal nutrition approach |
| Oesophageal dysmotility | Difficulty swallowing | Abnormalities on high resolution manometry | Dietary adjustment and eating behavioural modification. | Oral nutritional supplements if needed. NG feeding if malnourished. |
| Rumination syndrome | High pressure gastric contractions precede regurgitation/vomiting | Typical history. Concurrent impedance/manometry with meal provocation | Diaphragmatic breathing, baclofen, Nissens fundoplication (selected patients) | Optimised effortful oral feeding, short term bridging NJ to therapies only if malnourished |
| Cyclical vomiting syndrome and cannabis hyperemesis syndrome | Bouts of hyperemesis with intervals of normality. History of migraines. Relief from hot baths. | Clinical history is typical. Exclusion of other structural or central neural causes | May respond to tricyclics and migraine prophylaxis. Abstinence from cannabis. | Short bouts may need parenteral fluids/electrolytes. NJ likely to be unstable and unnecessary. |
| Chronic nausea and vomiting | Low-grade background constant nausea and vomiting | Clinical history and exclusion of other structural or central neural causes | Prokinetics, antiemetics, gut–brain neuromodulators | Optimised effortful oral feeding, avoid NJ unless malnourished. |
| Functional dyspepsia and gastroparesis | Overlapping spectrum of varying degrees of sensorimotor impairment of gastroduodenal function | Clinical history and solid meal gastric emptying test off medication affecting gastric emptying (but not based on gastric emptying study alone) | Pain management (avoid opioids), psychosocial support, buspirone, gut-brain neuromodulators including mirtazapine, pro-kinetics. | If malnourished with predominantly gastric muscle failure (gastroparesis), then trial of NJ with view to longer term post-pyloric feeding tube. |
| CIPO and enteric (small bowel) dysmotility (ED) | Non-mechanically obstructed dilated small bowel (CIPO) or significantly abnormal small bowel manometry or transit (ED) | CIPO—dilated small bowel radiologically. ED—small bowel manometry or abnormal transit. Full thickness biopsy if undergoing venting surgery. | Prokinetics, small intestinal bacterial overgrowth therapy, non-opioid analgesia with gut–brain neuromodulators | CIPO more likely to need parenteral nutrition than ED which should be manageable with optimised effortful oral or enteral feed. |
| Centrally mediated abdominal pain and narcotic bowel syndrome (NBS) | Chronic continuous abdominal pain with neuropathic features. Escalating opioid doses in NBS. | Clinical history and exclusion of other causes. | Non-opioid analgesics (eg, duloxetine). Opioid stabilisation and reduction. Mu-opioid antagonists. | Avoid enteral tube and parenteral feeding. |
| Somatoform disorder/central sensitivity syndrome | Overlapping multiple functional symptom syndromes | Psychiatric evaluation | Clinical psychology/liaison psychiatry. Central neuromodulators | Avoid iatrogenesis due to escalating invasive approaches. |
| Avoidant restrictive food intake disorder | Restrictive and avoidant behaviours not body image driven, but anxiety, fear, food related symptom and fixed (eg, health) beliefs | Psychiatric evaluation. | Clinical psychology and liaison psychiatry input | If severely malnourished may need short-term bridging enteral tube feeding to therapies but need not be post-pyloric. |
CIPO, chronic intestinal pseudo-obstruction; ED, enteric dysmotility; NBS, narcotic bowel syndrome; NG, nasogastric; NJ, nasojejunal.