Constipation and ObstipationAPPROACH

ABDOMINAL AND GASTROINTESTINAL · 19 SECTIONS

⚲

604 items

☷ Legend

⚲

Resuscitation and Universal Approaches9▾

Chest and Cardiovascular12▾

Respiratory11▾

Abdominal and Gastrointestinal24▾

Abdominal Distension Abdominal Pain, Undifferentiated Acute Abdominal Pain (general)Suspected Incarcerated Or Strangulated Hernia Pancreatitis Concern Biliary Colic And Cholecystitis Concern Appendicitis Concern Diverticulitis Concern Rectal Pain And Anorectal Complaints Dysphagia And Food Bolus Impaction Foreign Body Ingestion Refractory Vomiting And Recurrent Vomiting Syndromes Cannabis Associated Hyperemesis Upper Gastrointestinal Bleeding Symptoms (melena)Lower Gastrointestinal Bleeding And Hematochezia Constipation And Obstipation Diarrhea Acute Hepatitis And Jaundice Concern Right Upper Quadrant Pain Epigastric Pain Left Upper Quadrant Pain Right Lower Quadrant Pain Left Lower Quadrant Pain Suprapubic Pain

Renal and Urinary7▾

Neurologic11▾

Back and Neck8▾

Women's Health, Pregnancy, and GU11▾

Infectious Disease and Fever Syndromes11▾

Allergy and Dermatology7▾

Musculoskeletal and Extremities14▾

Trauma and Wounds14▾

ENT, Eye, Dental10▾

Endocrine, Metabolic, and Abnormal Labs9▾

Toxicology and Behavioral14▾

Pediatrics16▾

Environmental and Exposure4▾

01History/hx84

HPI overview

›Core symptom characterization

›Constipation definition

›Decreased stool frequency

›Difficult stool passage

›Obstipation definition

›Failure to pass stool

›Failure to pass flatus

›Time course

›Acute

›Subacute or chronic

OPQRST

›Onset

›First day without bowel movement

›Last normal bowel movement pattern

›Provocation and palliation

›Worse with

›Oral intake

›Opioids

›Relief with

›Laxatives

›Enemas

›Quality

›Stool consistency pattern

›Hard stools

›Pellet stools

›Pain quality pattern

›Crampy

›Constant

›Region and radiation

›Pain location

›Diffuse abdominal

›Lower abdominal

›Radiation pattern

›Back

›Groin

›Severity

›Pain severity trend

›Stable

›Escalating

›Functional impact

›Unable to tolerate oral intake

›Unable to sleep

›Timing

›Intermittent pattern

›Colicky waves

›Postprandial worsening

›Progressive pattern

›Increasing distension

›Decreasing flatus

Associated symptoms

›Gastrointestinal

›Nausea

›Vomiting

›Abdominal distension

›Hematochezia

›Melena

›Systemic

›Fever

›Weight loss

›Anorexia

›Genitourinary

›Urinary retention

›Dysuria

›Neurologic

›New leg weakness

›Saddle anesthesia

Baseline bowel pattern

›Prior baseline

›Typical frequency

›Typical stool form

›Straining baseline

›Prior interventions

›Home laxatives used

›Prior disimpactions

Context and triggers

›Recent changes

›New medication

›Reduced mobility

›Reduced intake

›Recent procedures

›Abdominal or pelvic surgery

›Colonoscopy

Prior episodes

›Recurrence features

›Similar prior episodes

›Prior obstruction history

›Prior outcomes

›Prior admission

›Prior surgery

02Alarm Features/alarm42

Immediate escalation triggers

›Time critical features

›Peritonitis features

›Rebound tenderness

›Guarding rigidity

›Hemodynamic instability

›Hypotension

›Altered mental status

›Severe vomiting

›Bilious

›Feculent

High risk historical features

›Obstruction and ischemia risk

›Obstipation

›Rapidly progressive distension

›Prior abdominal surgery

›Known hernia

›Malignancy risk

›Unintentional weight loss

›Change in stool caliber

›Iron deficiency anemia history

›Spinal cord compression risk

›Urinary retention

›New lower extremity neurologic symptoms

Vital sign danger patterns

›Sepsis pattern

›Fever

›Tachycardia

›Hypotension

›Pain out of proportion pattern

›Severe pain with minimal tenderness

›Rising lactate pattern

High risk exam findings

›Abdominal exam red flags

›Peritoneal signs

›Focal tender mass

›Hernia with tenderness

›Rectal exam red flags

›Gross blood

›Suspected rectal mass

High risk populations

›Increased complication risk

›Older adult

›Immunocompromised

›Anticoagulated

›Pregnancy

›Postoperative

03Medications/meds27

Constipating medications

›Medication contributors

›Opioids

›Anticholinergics

›Calcium channel blockers

›Tricyclic antidepressants

›Antipsychotics

›Iron

›Calcium supplements

›5 HT3 antagonists

›Antihistamines

Bowel regimen history

›Recent bowel agents

›Osmotic laxatives

›Stimulant laxatives

›Stool softeners

›Suppositories

›Enemas

Recent changes

›Timeline of medication changes

›New start within 7 days

›Dose increase within 7 days

›Missed usual laxatives

Contraindications and interaction traps

›Laxative safety flags

›Magnesium containing products

›Renal impairment concern

›Hypermagnesemia risk

›Sodium phosphate enemas

›Chronic kidney disease concern

›Heart failure concern

04Diet/diet12

Intake pattern

›Recent intake

›Reduced oral intake

›Reduced fiber intake

›High dairy pattern

Hydration indicators

›Volume status clues

›Reduced fluid intake

›Diuretic use pattern

›Dark urine history

Exposures

›Constipation related exposures

›Caffeine excess

›Alcohol excess

›Travel diet change

05Review of Systems/ros25

Gastrointestinal

›GI symptoms

›Abdominal pain

›Distension

›Nausea

›Vomiting

›Flatus pattern

›Rectal bleeding

Constitutional and infection

›Systemic symptoms

›Fever

›Chills

›Weight loss

›Night sweats

Genitourinary

›GU symptoms

›Urinary retention

›Dysuria

›Hematuria

Neurologic

›Neuro symptoms

›New weakness

›Sensory change

›Saddle anesthesia

›Back pain

Endocrine and metabolic

›Metabolic symptoms

›Heat or cold intolerance

›Polyuria

›Polydipsia

06Collateral History and Family History/chafh13

Collateral source

›Source and reliability

›Family or caregiver report

›Facility report

›Medication list confirmation

Family history

›Heritable and family risks

›Colorectal cancer

›Inflammatory bowel disease

›Celiac disease

›Endocrinopathies

Social supports

›Discharge reliability

›Ability to obtain medications

›Ability to hydrate

›Ability to return for worsening

07Risk Factors/rf25

Mechanical obstruction risks

›Predisposition to obstruction

›Prior abdominal surgery

›Known hernia

›Known malignancy

›Prior volvulus

Functional constipation risks

›Predisposition to slowed transit

›Low mobility

›Dehydration

›Low fiber diet

›Limited toileting access

Secondary medical risks

›Predisposition to secondary causes

›Hypothyroidism

›Hypercalcemia

›Diabetes mellitus

›Parkinson disease

›Multiple sclerosis

Medication risks

›High risk drug exposures

›Opioid therapy

›Anticholinergic burden

›Psychotropic polypharmacy

Special populations

›Higher complication risk groups

›Older adult frailty

›Pregnancy and postpartum

›Pediatrics

›Spinal cord injury

08Differential Diagnosis/ddx60

Life threatening

›Cannot miss

›Large bowel obstruction

›Progressive distension

›Obstipation

›Small bowel obstruction

›Colicky pain

›Bilious vomiting

›Volvulus

›Rapid distension

›Severe pain

›Bowel ischemia

›Pain out of proportion

›Rising lactate

›Perforated viscus

›Peritonitis

›Free air concern

›Toxic megacolon

›Systemic toxicity

›Marked colonic dilation

›Stercoral colitis

›Severe constipation history

›Focal abdominal tenderness

›Cauda equina syndrome

›Urinary retention

›Saddle anesthesia

›Abdominal aortic aneurysm

›Back or abdominal pain

›Hypotension

Common

›Frequent etiologies

›Functional constipation (K59.00)

›Low fiber intake

›Reduced activity

›Fecal impaction (K56.41)

›Rectal fullness

›Overflow diarrhea

›Opioid induced constipation (K59.03)

›Opioid exposure

›Poor response to fiber

›Constipation due to medication (K59.09)

›Anticholinergic exposure

›Calcium channel blocker exposure

›IBS with constipation (K58.1)

›Abdominal pain related to stooling

›Chronic fluctuating course

Less common

›Secondary and zebras

›Colorectal cancer (C18.9)

›Weight loss

›Anemia concern

›Hypothyroidism (E03.9)

›Fatigue

›Cold intolerance

›Hypercalcemia (E83.52)

›Polyuria

›Confusion

›Hirschsprung disease (Q43.1)

›Lifelong severe constipation

›Delayed meconium history

›Spinal cord lesion

›New neurologic deficits

›Back pain

09Past Medical History/pmh19

Gastrointestinal history

›Prior GI conditions

›Prior bowel obstruction

›Inflammatory bowel disease

›Prior diverticulitis

›Prior colorectal polyps

Surgeries and procedures

›Abdominal and pelvic surgeries

›Appendectomy

›Hernia repair

›Colectomy

›Gynecologic surgery

Chronic conditions

›Medical contributors

›Diabetes mellitus

›Hypothyroidism

›Chronic kidney disease

›Neurologic disease

Baseline function

›Baseline status

›Ambulation level

›Toileting independence

›Usual diet pattern

10Physical Exam/exam36

General and vitals

›General assessment

›Toxic appearance

›Dehydration signs

›Pain behavior pattern

›Vital sign interpretation

›Fever pattern

›Tachycardia pattern

›Hypotension pattern

Abdominal exam

›Abdomen

›Distension

›Bowel sounds pattern

›Tympany

›Diffuse tenderness

›Focal tenderness

›Peritoneal signs

Hernia and groin

›Hernia evaluation

›Inguinal

›Femoral

›Ventral

Rectal and perineal

›Digital rectal exam

›Stool in vault

›Hard mass consistent with impaction

›Gross blood

›Rectal tone

›Perineal inspection

›Fissure

›Hemorrhoids

Neurologic and spine

›Neuro screen for compression

›Lower extremity strength

›Sensation pattern

›Saddle sensation

›Reflexes pattern

Cardiopulmonary

›Volume status and complications

›Mucous membranes

›Capillary refill pattern

›Lung exam for aspiration concern

11Lab Studies/labs27

Core labs when secondary cause or complication concern

›Baseline evaluation

›CBC

›Leukocytosis pattern for infection or ischemia

›Anemia pattern for malignancy or bleeding

›Electrolytes

›Potassium abnormality

›Sodium abnormality

›Creatinine

›Dehydration pattern

›Laxative safety implications

Targeted labs for red flags

›Complication evaluation

›Lactate

›Ischemia concern when elevated

›Normal value does not exclude ischemia

›CRP

›Inflammatory pattern support

›Nonspecific limitation

›Pregnancy test

›Imaging selection implications

›Ectopic pregnancy mimic consideration

Secondary cause labs when indicated

›Metabolic and endocrine

›TSH

›Hypothyroidism screen

›Not an ED routine test without suggestive features

›Calcium

›Hypercalcemia screen

›Constipation contributor when elevated

12Imaging/img38

Scoring Systems

›Clinical tools and classification

›Bristol stool form scale

›Stool form pattern documentation

›Response tracking over time

›Rome IV constipation criteria

›Chronic constipation framework

›Not an acute obstruction rule out tool

MRI

›MRI indications

›Spine MRI

›Cauda equina concern

›Spinal epidural abscess concern

›Pelvic MRI

›Suspected pelvic mass with nondiagnostic CT

›Local protocol dependent

›CT abdomen and pelvis

›Indications

›Suspected bowel obstruction

›Suspected ischemia

›Suspected stercoral colitis

›Protocol considerations

›IV contrast when ischemia concern

›Oral contrast usually not required in ED obstruction evaluation

›Interpretation pearls

›Transition point for obstruction

›Pneumatosis portal venous gas concern

›Cautions

›Contrast nephropathy risk in severe CKD

›Radiation risk in pregnancy

Ultrasound

›Point of care ultrasound

›Bowel obstruction evaluation

›Dilated small bowel loops pattern

›To and fro peristalsis pattern

›AAA screening

›Aortic diameter screening

›Limited by bowel gas

›Bladder volume

›Urinary retention support

›Obstructive uropathy pathway trigger

13Special Tests/spec17

Bedside exams

›Rectal bedside evaluation

›Digital rectal exam findings

›Hard stool burden

›Empty vault despite severe symptoms

›Anoscopy when bleeding

›Hemorrhoids identification

›Fissure identification

Procedural diagnostics

›Nasogastric decompression response

›High output gastric drainage

›Symptom relief supports obstruction physiology

Specialty tests when indicated

›Endoscopy and contrast studies

›Water soluble contrast challenge

›Partial small bowel obstruction pathway

›Local protocol dependent

›Colonoscopy

›Malignancy evaluation pathway

›Not for unstable patients

14ECG/ecg9

Indications

›ECG utility

›Significant electrolyte abnormalities concern

›Syncope presyncope during straining history

Findings to monitor

›Electrolyte related patterns

›Hypokalemia related changes

›Hyperkalemia related changes

›Arrhythmia screening

›Atrial fibrillation

›Bradyarrhythmia

15Assessment/ax31

Working diagnosis

›Primary problem list

›Constipation (K59.00)

›No obstruction features

›Benign exam pattern

›Fecal impaction (K56.41)

›Rectal stool burden

›Overflow diarrhea possibility

›Suspected bowel obstruction (K56.609)

›Obstipation

›Distension with vomiting

Severity and risk stratification

›High risk features present

›Peritoneal signs

›Systemic toxicity

›Significant dehydration

›Low risk features present

›Passing flatus

›Tolerating oral intake

Complications to exclude

›Complications

›Bowel ischemia

›Pain out of proportion

›Metabolic acidosis pattern

›Perforation

›Free air concern

›Peritonitis

›Stercoral colitis

›CT colitis findings

›Fecaloma concern

Diagnostic uncertainty

›Alternative diagnoses

›Appendicitis

›Diverticulitis

›Renal colic

16Plan/plan78

First 5 minutes

›Initial stabilization workflow

›Monitoring

›Cardiac monitor for unstable or toxic appearance

›Pulse oximetry

›Vascular access

›IV access for dehydration or vomiting

›Two large bore IV for shock pattern

›Immediate escalation

›If peritonitis, immediate surgical consult

›If shock, resuscitation bay transfer

Diagnostic sequencing

›Test strategy

›Low risk constipation

›No routine imaging

›Focus on rectal exam and response to therapy

›Suspected obstruction or ischemia

›CT abdomen and pelvis pathway

›Lactate and CBC pathway

Therapeutics

›Hydration and symptom control

›IV fluids

›Isotonic crystalloid bolus for dehydration

›Reassessment after each bolus

›Antiemetic

›Ondansetron ODT 4 mg

›Ondansetron IV 4 mg

›Oral laxatives for low risk constipation

›Polyethylene glycol

›17 g in fluid once daily

›Up to 34 g once daily short term if severe

›Lactulose

›15 mL to 30 mL orally once to twice daily

›Flatulence and cramping risk

›Senna

›8.6 mg tablets

›2 tablets at bedtime

›Bisacodyl oral

›5 mg to 10 mg once daily

›Avoid in suspected obstruction

›Rectal therapy when rapid effect needed

›Bisacodyl suppository

›10 mg rectally once

›Onset within hours

›Glycerin suppository

›One suppository rectally

›Useful in pregnancy

›Enemas

›Mineral oil enema

›Warm water enema

›Avoid sodium phosphate enema in CKD or heart failure

›Fecal impaction pathway

›Manual disimpaction

›Topical lidocaine jelly

›Analgesia or procedural sedation if needed

›Post disimpaction regimen

›Polyethylene glycol daily

›Stimulant laxative short term

›Suspected bowel obstruction pathway

›Bowel rest

›NPO

›NG tube if persistent vomiting or significant distension

›Resuscitation

›Isotonic crystalloid

›Electrolyte correction

›Consultation

›General surgery early

›GI consultation for suspected malignancy obstruction when stable

›Antibiotics when complication concern

›If perforation concern, broad spectrum per local protocol

›If ischemia concern, broad spectrum per local protocol

Reassessment loop

›Interval reassessment

›After each intervention

›Pain trajectory

›Nausea and vomiting trajectory

›Objective outputs

›Passage of stool

›Passage of flatus

›Escalation triggers

›New peritoneal signs

›Rising lactate or worsening acidosis

17Disposition/dispo31

ICU criteria

›Critical care needs

›Septic shock pattern

›Hypotension after fluids

›Vasopressor requirement

›Suspected bowel ischemia with instability

›Rising lactate with hypotension

›Peritonitis

Inpatient admission criteria

›Admission indications

›Confirmed bowel obstruction

›CT obstruction findings

›Persistent vomiting

›Stercoral colitis

›CT colitis findings

›Systemic inflammatory response

›Failed ED disimpaction

›Persistent severe symptoms

›Inability to tolerate oral intake

Observation pathway criteria

›Short stay candidates

›Moderate dehydration responding to fluids

›Partial obstruction under protocol

›Need for repeated enemas with monitoring

Discharge criteria

›Safe discharge features

›No alarm features

›Benign abdominal exam

›Tolerating oral intake

›Stool passage or clear improvement

›Reliable follow up and return ability

Follow up timing

›Follow up plan

›Primary care within 3 to 7 days

›GI referral within weeks for chronic or recurrent

›Urgent referral for cancer concern features

18Discharge Instructions/di24

Copy discharge instructions

›Diagnosis summary

›Constipation

›No signs of bowel blockage found today

›Medications

›Polyethylene glycol 17 g in fluid daily

›Senna 2 tablets at bedtime as needed

›Avoid additional laxatives if vomiting or worsening abdominal pain

›Hydration and diet

›Increase fluids

›Increase fiber gradually

›Activity

›Walking daily if able

›Avoid straining

›Follow up

›Primary care within 3 to 7 days

›Earlier follow up if symptoms persist

›Return to emergency

›Severe or worsening abdominal pain

›Vomiting that does not stop

›Cannot pass gas

›Fever

›Blood in stool

›New weakness or numbness

›Trouble urinating

19References/r6

Guidelines and key sources

›Core references

›American Gastroenterological Association guideline on constipation 2013

›American College of Gastroenterology clinical guideline on chronic idiopathic constipation 2023

›Rome IV criteria for functional bowel disorders 2016

›American Society of Colon and Rectal Surgeons practice parameters for constipation 2016

›World Society of Emergency Surgery guidelines for acute colonic pseudo obstruction and volvulus 2017

Evidence & Review

Reviewed by SymptomDx Medical Team · Last reviewed February 24, 2026

SymptomDx is an educational tool for medical professionals. It does not replace clinical judgment. Verify all clinical data and drug dosages with authoritative sources.

Constipation and ObstipationAPPROACH

ABDOMINAL AND GASTROINTESTINAL · 19 SECTIONS

⚲

604 items

☷ Legend

⚲

Resuscitation and Universal Approaches9▾

Chest and Cardiovascular12▾

Respiratory11▾

Abdominal and Gastrointestinal24▾

Renal and Urinary7▾

Neurologic11▾

Back and Neck8▾

Women's Health, Pregnancy, and GU11▾

Infectious Disease and Fever Syndromes11▾

Allergy and Dermatology7▾

Musculoskeletal and Extremities14▾

Trauma and Wounds14▾

ENT, Eye, Dental10▾

Endocrine, Metabolic, and Abnormal Labs9▾

Toxicology and Behavioral14▾

Pediatrics16▾

Environmental and Exposure4▾

01History/hx84

HPI overview

›Core symptom characterization

›Constipation definition

›Decreased stool frequency

›Difficult stool passage

›Obstipation definition

›Failure to pass stool

›Failure to pass flatus

›Time course

›Acute

›Subacute or chronic

OPQRST

›Onset

›First day without bowel movement

›Last normal bowel movement pattern

›Provocation and palliation

›Worse with

›Oral intake

›Opioids

›Relief with

›Laxatives

›Enemas

›Quality

›Stool consistency pattern

›Hard stools

›Pellet stools

›Pain quality pattern

›Crampy

›Constant

›Region and radiation

›Pain location

›Diffuse abdominal

›Lower abdominal

›Radiation pattern

›Back

›Groin

›Severity

›Pain severity trend

›Stable

›Escalating

›Functional impact

›Unable to tolerate oral intake

›Unable to sleep

›Timing

›Intermittent pattern

›Colicky waves

›Postprandial worsening

›Progressive pattern

›Increasing distension

›Decreasing flatus

Associated symptoms

›Gastrointestinal

›Nausea

›Vomiting

›Abdominal distension

›Hematochezia

›Melena

›Systemic

›Fever

›Weight loss

›Anorexia

›Genitourinary

›Urinary retention

›Dysuria

›Neurologic

›New leg weakness

›Saddle anesthesia

Baseline bowel pattern

›Prior baseline

›Typical frequency

›Typical stool form

›Straining baseline

›Prior interventions

›Home laxatives used

›Prior disimpactions

Context and triggers

›Recent changes

›New medication

›Reduced mobility

›Reduced intake

›Recent procedures

›Abdominal or pelvic surgery

›Colonoscopy

Prior episodes

›Recurrence features

›Similar prior episodes

›Prior obstruction history

›Prior outcomes

›Prior admission

›Prior surgery

02Alarm Features/alarm42

Immediate escalation triggers

›Time critical features

›Peritonitis features

›Rebound tenderness

›Guarding rigidity

›Hemodynamic instability

›Hypotension

›Altered mental status

›Severe vomiting

›Bilious

›Feculent

High risk historical features

›Obstruction and ischemia risk

›Obstipation

›Rapidly progressive distension

›Prior abdominal surgery

›Known hernia

›Malignancy risk

›Unintentional weight loss

›Change in stool caliber

›Iron deficiency anemia history

›Spinal cord compression risk

›Urinary retention

›New lower extremity neurologic symptoms

Vital sign danger patterns

›Sepsis pattern

›Fever

›Tachycardia

›Hypotension

›Pain out of proportion pattern

›Severe pain with minimal tenderness

›Rising lactate pattern

High risk exam findings

›Abdominal exam red flags

›Peritoneal signs

›Focal tender mass

›Hernia with tenderness

›Rectal exam red flags

›Gross blood

›Suspected rectal mass

High risk populations

›Increased complication risk

›Older adult

›Immunocompromised

›Anticoagulated

›Pregnancy

›Postoperative

03Medications/meds27

Constipating medications

›Medication contributors

›Opioids

›Anticholinergics

›Calcium channel blockers

›Tricyclic antidepressants

›Antipsychotics

›Iron

›Calcium supplements

›5 HT3 antagonists

›Antihistamines

Bowel regimen history

›Recent bowel agents

›Osmotic laxatives

›Stimulant laxatives

›Stool softeners

›Suppositories

›Enemas

Recent changes

›Timeline of medication changes

›New start within 7 days

›Dose increase within 7 days

›Missed usual laxatives

Contraindications and interaction traps

›Laxative safety flags

›Magnesium containing products

›Renal impairment concern

›Hypermagnesemia risk

›Sodium phosphate enemas

›Chronic kidney disease concern

›Heart failure concern

04Diet/diet12

Intake pattern

›Recent intake

›Reduced oral intake

›Reduced fiber intake

›High dairy pattern

Hydration indicators

›Volume status clues

›Reduced fluid intake

›Diuretic use pattern

›Dark urine history

Exposures

›Constipation related exposures

›Caffeine excess

›Alcohol excess

›Travel diet change

05Review of Systems/ros25

Gastrointestinal

›GI symptoms

›Abdominal pain

›Distension

›Nausea

›Vomiting

›Flatus pattern

›Rectal bleeding

Constitutional and infection

›Systemic symptoms

›Fever

›Chills

›Weight loss

›Night sweats

Genitourinary

›GU symptoms

›Urinary retention

›Dysuria

›Hematuria

Neurologic

›Neuro symptoms

›New weakness

›Sensory change

›Saddle anesthesia

›Back pain

Endocrine and metabolic

›Metabolic symptoms

›Heat or cold intolerance

›Polyuria

›Polydipsia

06Collateral History and Family History/chafh13

Collateral source

›Source and reliability

›Family or caregiver report

›Facility report

›Medication list confirmation

Family history

›Heritable and family risks

›Colorectal cancer

›Inflammatory bowel disease

›Celiac disease

›Endocrinopathies

Social supports

›Discharge reliability

›Ability to obtain medications

›Ability to hydrate

›Ability to return for worsening

07Risk Factors/rf25

Mechanical obstruction risks

›Predisposition to obstruction

›Prior abdominal surgery

›Known hernia

›Known malignancy

›Prior volvulus

Functional constipation risks

›Predisposition to slowed transit

›Low mobility

›Dehydration

›Low fiber diet

›Limited toileting access

Secondary medical risks

›Predisposition to secondary causes

›Hypothyroidism

›Hypercalcemia

›Diabetes mellitus

›Parkinson disease

›Multiple sclerosis

Medication risks

›High risk drug exposures

›Opioid therapy

›Anticholinergic burden

›Psychotropic polypharmacy

Special populations

›Higher complication risk groups

›Older adult frailty

›Pregnancy and postpartum

›Pediatrics

›Spinal cord injury

08Differential Diagnosis/ddx60

Life threatening

›Cannot miss

›Large bowel obstruction

›Progressive distension

›Obstipation

›Small bowel obstruction

›Colicky pain

›Bilious vomiting

›Volvulus

›Rapid distension

›Severe pain

›Bowel ischemia

›Pain out of proportion

›Rising lactate

›Perforated viscus

›Peritonitis

›Free air concern

›Toxic megacolon

›Systemic toxicity

›Marked colonic dilation

›Stercoral colitis

›Severe constipation history

›Focal abdominal tenderness

›Cauda equina syndrome

›Urinary retention

›Saddle anesthesia

›Abdominal aortic aneurysm

›Back or abdominal pain

›Hypotension

Common

›Frequent etiologies

›Functional constipation (K59.00)

›Low fiber intake

›Reduced activity

›Fecal impaction (K56.41)

›Rectal fullness

›Overflow diarrhea

›Opioid induced constipation (K59.03)

›Opioid exposure

›Poor response to fiber

›Constipation due to medication (K59.09)

›Anticholinergic exposure

›Calcium channel blocker exposure

›IBS with constipation (K58.1)

›Abdominal pain related to stooling

›Chronic fluctuating course

Less common

›Secondary and zebras

›Colorectal cancer (C18.9)

›Weight loss

›Anemia concern

›Hypothyroidism (E03.9)

›Fatigue

›Cold intolerance

›Hypercalcemia (E83.52)

›Polyuria

›Confusion

›Hirschsprung disease (Q43.1)

›Lifelong severe constipation

›Delayed meconium history

›Spinal cord lesion

›New neurologic deficits

›Back pain

09Past Medical History/pmh19

Gastrointestinal history

›Prior GI conditions

›Prior bowel obstruction

›Inflammatory bowel disease

›Prior diverticulitis

›Prior colorectal polyps

Surgeries and procedures

›Abdominal and pelvic surgeries

›Appendectomy

›Hernia repair

›Colectomy

›Gynecologic surgery

Chronic conditions

›Medical contributors

›Diabetes mellitus

›Hypothyroidism

›Chronic kidney disease

›Neurologic disease

Baseline function

›Baseline status

›Ambulation level

›Toileting independence

›Usual diet pattern

10Physical Exam/exam36

General and vitals

›General assessment

›Toxic appearance

›Dehydration signs

›Pain behavior pattern

›Vital sign interpretation

›Fever pattern

›Tachycardia pattern

›Hypotension pattern

Abdominal exam

›Abdomen

›Distension

›Bowel sounds pattern

›Tympany

›Diffuse tenderness

›Focal tenderness

›Peritoneal signs

Hernia and groin

›Hernia evaluation

›Inguinal

›Femoral

›Ventral

Rectal and perineal

›Digital rectal exam

›Stool in vault

›Hard mass consistent with impaction

›Gross blood

›Rectal tone

›Perineal inspection

›Fissure

›Hemorrhoids

Neurologic and spine

›Neuro screen for compression

›Lower extremity strength

›Sensation pattern

›Saddle sensation

›Reflexes pattern

Cardiopulmonary

›Volume status and complications

›Mucous membranes

›Capillary refill pattern

›Lung exam for aspiration concern

11Lab Studies/labs27

Core labs when secondary cause or complication concern

›Baseline evaluation

›CBC

›Leukocytosis pattern for infection or ischemia

›Anemia pattern for malignancy or bleeding

›Electrolytes

›Potassium abnormality

›Sodium abnormality

›Creatinine

›Dehydration pattern

›Laxative safety implications

Targeted labs for red flags

›Complication evaluation

›Lactate

›Ischemia concern when elevated

›Normal value does not exclude ischemia

›CRP

›Inflammatory pattern support

›Nonspecific limitation

›Pregnancy test

›Imaging selection implications

›Ectopic pregnancy mimic consideration

Secondary cause labs when indicated

›Metabolic and endocrine

›TSH

›Hypothyroidism screen

›Not an ED routine test without suggestive features

›Calcium

›Hypercalcemia screen

›Constipation contributor when elevated

12Imaging/img38

Scoring Systems

›Clinical tools and classification

›Bristol stool form scale

›Stool form pattern documentation

›Response tracking over time

›Rome IV constipation criteria

›Chronic constipation framework

›Not an acute obstruction rule out tool

MRI

›MRI indications

›Spine MRI

›Cauda equina concern

›Spinal epidural abscess concern

›Pelvic MRI

›Suspected pelvic mass with nondiagnostic CT

›Local protocol dependent

›CT abdomen and pelvis

›Indications

›Suspected bowel obstruction

›Suspected ischemia

›Suspected stercoral colitis

›Protocol considerations

›IV contrast when ischemia concern

›Oral contrast usually not required in ED obstruction evaluation

›Interpretation pearls

›Transition point for obstruction

›Pneumatosis portal venous gas concern

›Cautions

›Contrast nephropathy risk in severe CKD

›Radiation risk in pregnancy

Ultrasound

›Point of care ultrasound

›Bowel obstruction evaluation

›Dilated small bowel loops pattern

›To and fro peristalsis pattern

›AAA screening

›Aortic diameter screening

›Limited by bowel gas

›Bladder volume

›Urinary retention support

›Obstructive uropathy pathway trigger

13Special Tests/spec17

Bedside exams

›Rectal bedside evaluation

›Digital rectal exam findings

›Hard stool burden

›Empty vault despite severe symptoms

›Anoscopy when bleeding

›Hemorrhoids identification

›Fissure identification

Procedural diagnostics

›Nasogastric decompression response

›High output gastric drainage

›Symptom relief supports obstruction physiology

Specialty tests when indicated

›Endoscopy and contrast studies

›Water soluble contrast challenge

›Partial small bowel obstruction pathway

›Local protocol dependent

›Colonoscopy

›Malignancy evaluation pathway

›Not for unstable patients

14ECG/ecg9

Indications

›ECG utility

›Significant electrolyte abnormalities concern

›Syncope presyncope during straining history

Findings to monitor

›Electrolyte related patterns

›Hypokalemia related changes

›Hyperkalemia related changes

›Arrhythmia screening

›Atrial fibrillation

›Bradyarrhythmia

15Assessment/ax31

Working diagnosis

›Primary problem list

›Constipation (K59.00)

›No obstruction features

›Benign exam pattern

›Fecal impaction (K56.41)

›Rectal stool burden

›Overflow diarrhea possibility

›Suspected bowel obstruction (K56.609)

›Obstipation

›Distension with vomiting

Severity and risk stratification

›High risk features present

›Peritoneal signs

›Systemic toxicity

›Significant dehydration

›Low risk features present

›Passing flatus

›Tolerating oral intake

Complications to exclude

›Complications

›Bowel ischemia

›Pain out of proportion

›Metabolic acidosis pattern

›Perforation

›Free air concern

›Peritonitis

›Stercoral colitis

›CT colitis findings

›Fecaloma concern

Diagnostic uncertainty

›Alternative diagnoses

›Appendicitis

›Diverticulitis

›Renal colic

16Plan/plan78

First 5 minutes

›Initial stabilization workflow

›Monitoring

›Cardiac monitor for unstable or toxic appearance

›Pulse oximetry

›Vascular access

›IV access for dehydration or vomiting

›Two large bore IV for shock pattern

›Immediate escalation

›If peritonitis, immediate surgical consult

›If shock, resuscitation bay transfer

Diagnostic sequencing

›Test strategy

›Low risk constipation

›No routine imaging

›Focus on rectal exam and response to therapy

›Suspected obstruction or ischemia

›CT abdomen and pelvis pathway

›Lactate and CBC pathway

Therapeutics

›Hydration and symptom control

›IV fluids

›Isotonic crystalloid bolus for dehydration

›Reassessment after each bolus

›Antiemetic

›Ondansetron ODT 4 mg

›Ondansetron IV 4 mg

›Oral laxatives for low risk constipation

›Polyethylene glycol

›17 g in fluid once daily

›Up to 34 g once daily short term if severe

›Lactulose

›15 mL to 30 mL orally once to twice daily

›Flatulence and cramping risk

›Senna

›8.6 mg tablets

›2 tablets at bedtime

›Bisacodyl oral

›5 mg to 10 mg once daily

›Avoid in suspected obstruction

›Rectal therapy when rapid effect needed

›Bisacodyl suppository

›10 mg rectally once

›Onset within hours

›Glycerin suppository

›One suppository rectally

›Useful in pregnancy

›Enemas

›Mineral oil enema

›Warm water enema

›Avoid sodium phosphate enema in CKD or heart failure

›Fecal impaction pathway

›Manual disimpaction

›Topical lidocaine jelly

›Analgesia or procedural sedation if needed

›Post disimpaction regimen

›Polyethylene glycol daily

›Stimulant laxative short term

›Suspected bowel obstruction pathway

›Bowel rest

›NPO

›NG tube if persistent vomiting or significant distension

›Resuscitation

›Isotonic crystalloid

›Electrolyte correction

›Consultation

›General surgery early

›GI consultation for suspected malignancy obstruction when stable

›Antibiotics when complication concern

›If perforation concern, broad spectrum per local protocol

›If ischemia concern, broad spectrum per local protocol

Reassessment loop

›Interval reassessment

›After each intervention

›Pain trajectory

›Nausea and vomiting trajectory

›Objective outputs

›Passage of stool

›Passage of flatus

›Escalation triggers

›New peritoneal signs

›Rising lactate or worsening acidosis

17Disposition/dispo31

ICU criteria

›Critical care needs

›Septic shock pattern

›Hypotension after fluids

›Vasopressor requirement

›Suspected bowel ischemia with instability

›Rising lactate with hypotension

›Peritonitis

Inpatient admission criteria

›Admission indications

›Confirmed bowel obstruction

›CT obstruction findings

›Persistent vomiting

›Stercoral colitis

›CT colitis findings

›Systemic inflammatory response

›Failed ED disimpaction

›Persistent severe symptoms

›Inability to tolerate oral intake

Observation pathway criteria

›Short stay candidates

›Moderate dehydration responding to fluids

›Partial obstruction under protocol

›Need for repeated enemas with monitoring

Discharge criteria

›Safe discharge features

›No alarm features

›Benign abdominal exam

›Tolerating oral intake

›Stool passage or clear improvement

›Reliable follow up and return ability

Follow up timing

›Follow up plan

›Primary care within 3 to 7 days

›GI referral within weeks for chronic or recurrent

›Urgent referral for cancer concern features

18Discharge Instructions/di24

Copy discharge instructions

›Diagnosis summary

›Constipation

›No signs of bowel blockage found today

›Medications

›Polyethylene glycol 17 g in fluid daily

›Senna 2 tablets at bedtime as needed

›Avoid additional laxatives if vomiting or worsening abdominal pain

›Hydration and diet

›Increase fluids

›Increase fiber gradually

›Activity

›Walking daily if able

›Avoid straining

›Follow up

›Primary care within 3 to 7 days

›Earlier follow up if symptoms persist

›Return to emergency

›Severe or worsening abdominal pain

›Vomiting that does not stop

›Cannot pass gas

›Fever

›Blood in stool

›New weakness or numbness

›Trouble urinating

19References/r6

Guidelines and key sources

›Core references

›American Gastroenterological Association guideline on constipation 2013

›American College of Gastroenterology clinical guideline on chronic idiopathic constipation 2023

›Rome IV criteria for functional bowel disorders 2016

›American Society of Colon and Rectal Surgeons practice parameters for constipation 2016

›World Society of Emergency Surgery guidelines for acute colonic pseudo obstruction and volvulus 2017

Evidence & Review

Reviewed by SymptomDx Medical Team · Last reviewed February 24, 2026

SymptomDx is an educational tool for medical professionals. It does not replace clinical judgment. Verify all clinical data and drug dosages with authoritative sources.