Motility, in full.

Begin evaluation of abdominal pain with a rapid risk assessment: identify hemodynamic instability, signs of peritonitis, or pain out of proportion to examination findings, these patients need urgent resuscitation or surgical evaluation. Pursue specific life-threatening causes (ruptured AAA, aortic dissection, mesenteric ischemia, ectopic pregnancy, myocardial ischemia) when presentation and risk factors raise suspicion for them, rather than as a universal rule-out before assigning a GI cause. In stable patients, apply a localization-driven differential (RUQ/epigastric/LUQ/RLQ/LLQ/diffuse/periumbilical/suprapubic) with stepwise workup: history and exam with red flags (fever, protracted vomiting, syncope/presyncope, GI blood loss), labs (CBC, CRP, hepatobiliary markers, electrolytes/creatinine/glucose, urinalysis, lipase; pregnancy test in all premenopausal women, including those using reliable contraception; lactate when sepsis or mesenteric ischemia is suspected, may be normal early; ECG/troponin when a cardiac cause is suspected), imaging by location (ultrasound first for RUQ pain; CT with IV contrast for RLQ, LLQ, and generalized pain; CTA when mesenteric ischemia is suspected; in pregnancy, ultrasound first with MRI when ultrasound is inconclusive), then endoscopy and specialty referral by suspicion.

Diagnosis: use a positive diagnostic strategy based on Rome IV criteria rather than a strategy of exclusion (strong for cost-effectiveness, high quality; consensus for time-to-therapy), and categorize by IBS subtype (consensus). In patients with IBS and diarrhea symptoms: check celiac serology (strong, moderate) and, in those WITHOUT alarm features, fecal calprotectin (or fecal lactoferrin) plus CRP to rule out IBD (strong; moderate quality for CRP/calprotectin, very low for lactoferrin). Recommend AGAINST routine stool testing for enteric pathogens (conditional, low) and AGAINST routine colonoscopy in patients younger than 45 without warning signs (conditional, low). Anorectal physiology testing only when symptoms suggest a pelvic floor disorder and/or for refractory constipation not responding to standard medical therapy (consensus). Treatment, all subtypes: soluble, not insoluble, fiber (strong, moderate); a LIMITED trial of a low-FODMAP diet (conditional, very low); gut-directed psychotherapies for global symptoms (conditional, very low); TCAs for global symptoms (strong, moderate); peppermint suggested (conditional, low); antispasmodics for abdominal pain (conditional, low); AGAINST probiotics (conditional, very low), AGAINST fecal transplant (strong, very low). IBS-C: chloride channel activators (strong, moderate) and guanylate cyclase activators (strong, high); AGAINST PEG products for global IBS-C symptoms (conditional, low); tegaserod reserved for women younger than 65 with ≤1 cardiovascular risk factor who have not adequately responded to secretagogues (strong/conditional, low). IBS-D: rifaximin (strong, moderate); alosetron only for women with severe IBS-D who have failed conventional therapy (conditional, low); mixed opioid agonists/antagonists, i.e. eluxadoline (conditional, moderate); AGAINST bile acid sequestrants (conditional, very low).

In DGBI where pain is dominant, a central neuromodulator is a logical part of the treatment profile. (1) TCAs are first-line when pain dominates: low-to-modest dosages have the most convincing evidence for chronic GI pain. Start low (10 mg/d helps patients get past early side effects), titrate within 4-6 weeks to 25-75 mg/d at night, and increase further to 100-150 mg/d only if no disturbing side effects develop; evidence for analgesic effect at <25 mg/d is lacking. Tertiary amines (amitriptyline, imipramine) are more anticholinergic/antihistaminic and may be chosen when constipating/sedating effects are useful (IBS-D, disturbed sleep); secondary amines (nortriptyline, desipramine) when those effects are unwanted (IBS-C, or pain with constipation). The TCA class is first-line for IBS, especially IBS-D. (2) SNRIs (duloxetine 30-90 mg, venlafaxine 75-225 mg with >225 mg needed for noradrenergic pain effect, milnacipran) 'may have at least equal benefit as TCAs' for chronic GI pain, but this is extrapolated from fibromyalgia, migraine, widespread body pain and neuropathy; they 'have not been adequately tested for chronic GI pain' and have not been adequately studied in IBS. Their advantage is the absence of anticholinergic/antihistaminic effects that preclude adequate TCA dosing; start in the low-dose range for the first week because nausea is common. SNRIs may be favored for IBS-C. (3) SSRIs are for anxiety, depression and phobic features, not pain: 'SSRIs can be considered in IBS if anxiety states, including hypervigilance, somatic symptom disorder, visceral anxiety, and maladaptive cognitions, are present, and the abdominal pain and diarrhea are not the dominant clinical features.' (4) Functional dyspepsia is treated by Rome IV subgroup. For PDS with early satiety, fullness and nausea predominating: buspirone, dosed as for anxiety, 30 mg/d divided 2-3 times daily, increasable to 60 mg/d (a 4-week trial reduced dyspeptic symptoms). Mirtazapine is 'a good treatment option for PDS when there is chronic nausea and vomiting, or weight loss', 15 mg in the evening for 8 weeks was superior to placebo in FD patients with weight loss and without coexisting anxiety or depression; usual range 15-45 mg in the evening. For EPS, studies mainly support TCAs (amitriptyline), either initially or after an unsuccessful PPI trial; the SNRI group 'can also be considered for patients with EPS who do not tolerate TCA treatment, although confirmatory studies are lacking.' (5) Functional heartburn and functional chest pain (after excluding GERD): 'There is insufficient evidence to recommend a particular class of central agent.' SSRIs have shown some benefit for esophageal pain; low-dose imipramine or amitriptyline 'can be considered,' but those studies are small and one was open-label; venlafaxine 75 mg extended-release at night beat placebo in a young cohort (20-29 years). (6) A comorbid dominant psychiatric diagnosis, identified by clinical assessment or questionnaires such as the HADS, 'may need to be a primary consideration when selecting a neuromodulator'; neuromodulators can alternatively be selected for their peripheral effects (disturbed bowel habit, chronic nausea). (7) Augmentation, reducing the dose of the first agent and adding a second, complementary treatment, is recommended when monotherapy is insufficient or dose-limited by side effects: an azapirone (dyspeptic features, prominent anxiety), a delta ligand (abdominal wall pain, comorbid fibromyalgia; pregabalin 150-600 mg/d, effect expected within a month), an SSRI (dominant anxiety/phobic features), an atypical antipsychotic (quetiapine 25-200 mg for pain with disturbed sleep, the psychiatric range of ≥200-400 mg/d is poorly tolerated; olanzapine/sulpiride for anxiety and nausea), bupropion (prominent fatigue/sleepiness), or a psychological treatment. (8) Behavioral therapy is positioned as an adjunct/augmentation, not as a co-equal mandatory arm: CBT where maladaptive cognitions and catastrophizing are present, DBT/EMDR with a history of PTSD or trauma, hypnosis/mindfulness/relaxation as alternatives; many RCTs support behavioral interventions 'as an adjunct to pharmacologic strategies,' and few studies compare behavioral alone against combination. (9) Continue treatment 6-12 months after treatment response to reduce relapse (empiric recommendation, extrapolated from major depression where 4-9 months is advised); consider longer-term treatment where ongoing psychosocial stress, positive family history, multiple prior episodes, or current psychiatric comorbidity exist. (10) Opioids should be avoided: there are no controlled data supporting opioids in chronic visceral pain, and their use carries substantial risk of opioid-induced constipation and narcotic bowel syndrome. (11) Implementation depends on communication: educate, provide a physiological rationale, address the patient's reluctance to take a 'psychiatric' drug, and involve the patient in medication choice, merely recommending the drug leads to refusal, nonadherence, or anxiety-driven side-effect reports.

Diagnose non-achalasia esophageal motility disorders on high-resolution manometry performed with the full CCv4.0 protocol, and treat the manometric pattern as a disorder only when it is accompanied by clinically relevant symptoms. The protocol requires both positions: supine (60-second adaptation, 30-second landmark/baseline, ten 5 mL wet swallows, one multiple rapid swallow of five 2 mL swallows at 2-3 second intervals) and upright at >=80 degrees (five 5 mL wet swallows plus a 200 mL rapid drink challenge); solid swallows, a solid test meal, or pharmacologic provocation (amyl nitrite, cholecystokinin) are added when standard swallows do not explain the symptom. IRP thresholds are manufacturer- and position-specific (for the Medtronic system, abnormal median IRP is >=15 mmHg supine and >=12 mmHg upright). CCv4.0 grades diagnoses as conclusive or inconclusive: distal esophageal spasm requires a normal median IRP plus >=20% premature contractions (distal latency <4.5 s with DCI >=450 mmHg*s*cm) AND clinically relevant dysphagia or non-cardiac chest pain; hypercontractile esophagus requires a normal median IRP plus >=20% hypercontractile supine swallows (DCI >8,000 mmHg*s*cm) AND clinically relevant dysphagia or non-cardiac chest pain, with mechanical obstruction excluded. Ineffective esophageal motility requires a normal IRP in both positions plus >70% ineffective swallows or >=50% failed peristalsis, where an ineffective swallow is weak (DCI 100-450), failed (DCI <100), or fragmented; 50-70% ineffective swallows is inconclusive and requires supportive testing. Absent contractility requires a normal median IRP in both supine and upright positions with 100% failed peristalsis, and because achalasia can present this way, provocative testing and adjunctive investigation are needed when there is any clinical suspicion of achalasia. Manometric EGJ outflow obstruction is never conclusive on manometry alone: it requires an elevated median IRP in BOTH the primary and secondary position plus >=20% of swallows with elevated intrabolus pressure, with peristalsis preserved; a conclusive, clinically relevant diagnosis additionally requires compatible symptoms (dysphagia or non-cardiac chest pain) AND at least one supportive investigation showing obstruction (timed barium esophagram with tablet and/or functional lumen imaging probe). An isolated elevated supine IRP, an isolated elevated upright IRP, or isolated elevated intrabolus pressure alone are each inconclusive and do not establish EGJOO. CCv4.0 is a diagnostic classification and does not issue treatment recommendations; therapy for these entities is not traceable to this document.

First exclude emergency/secondary causes (cauda equina/cord compression, fecal impaction with overflow) with a mandatory digital rectal exam, screen for eating disorder before dietary restriction, and classify the subtype (urge, passive, overflow, mixed) since it drives therapy. Work up loose-stool FI for inflammatory, infectious, and bile-acid drivers before labeling idiopathic. Manage with a stepwise ladder: optimize stool consistency (fiber, loperamide, bile-acid sequestrant, or TCA neuromodulator), pelvic floor PT plus biofeedback, skin protection and bridge devices, then escalate to surgical therapy. Prescribe the antimotility/neuromodulator agents with their indications, dosing, and safety limits: loperamide is first-line for loose-stool/urge FI, start low (e.g., 2 mg before meals or as needed) and titrate to stool consistency while staying within the FDA-approved maximum (8 mg/day OTC, 16 mg/day prescription), because the FDA warns that higher-than-recommended doses cause QT prolongation, torsades de pointes, and cardiac arrest; the TCA neuromodulator (e.g., amitriptyline, typically low-dose ~20 mg) is an off-label option reserved for loose-stool/idiopathic FI, and the AGS Beers Criteria recommend avoiding TCAs such as amitriptyline in older adults given their strong anticholinergic burden, sedation, orthostatic hypotension, and fall risk. Per the dedicated ASCRS 2023 fecal-incontinence guideline (updating ASCRS 2007, superseding reliance on ACG's broader 2021 anorectal-disorders guideline as the primary specialty source), sacral neuromodulation is a first-line surgical option for incontinent patients WITH OR WITHOUT a defined anal sphincter defect (conditional recommendation, low-quality evidence), it is not gated on documenting a sphincter defect. Sphincteroplasty remains appropriate for symptomatic patients with a defined external anal sphincter defect; repeat sphincteroplasty after a failed overlapping repair should generally be avoided in favor of other modalities. Antegrade continence enemas are an option before colostomy, which remains last resort.