Medical Term for Constipation
The medical term for difficulty passing stool is "constipation," which encompasses several specific subtypes including functional constipation, defecatory disorders (also called dyssynergia, dyschezia, or obstructed defecation), and constipation-predominant irritable bowel syndrome (IBS-C). 1
Core Definition
Constipation is medically defined as difficulty with or reduced frequency of bowel movements, often accompanied by straining during defecation or a feeling of incomplete evacuation 2. The condition manifests through:
- Infrequent bowel movements (≤2 per week)
- Hard, difficult-to-pass stools
- Excessive straining
- Sensation of incomplete evacuation
- Need for manual maneuvers (digital evacuation, perineal pressure) 1, 3
Clinical Classification Framework
The American Gastroenterological Association categorizes constipation into three primary functional subtypes based on colonic transit and anorectal function 1:
1. Defecatory Disorders
Also termed outlet obstruction, obstructed defecation, dyschezia, anismus, or pelvic floor dyssynergia. These involve impaired rectal evacuation from inadequate propulsive forces and/or increased resistance, including paradoxical contraction of pelvic floor muscles during attempted defecation 1.
2. Normal Transit Constipation (NTC)
Patients have normal anorectal function and normal colonic transit but experience constipation symptoms 1.
3. Slow Transit Constipation (STC)
Characterized by delayed colonic transit with reduced colonic propulsive activity, often showing marked reduction in colonic intrinsic nerves and interstitial cells of Cajal 1.
Important Distinctions
Chronic vs. Occasional: When symptoms persist rather than occur intermittently (such as during travel), the condition is termed "chronic constipation" 1. Occasional constipation refers to intermittent symptomatic alterations in bowel habit lasting days to weeks 4.
IBS-C vs. Functional Constipation: The key differentiator is the presence of recurrent abdominal pain in IBS-C, though this distinction exists on a spectrum rather than as an absolute boundary 2, 5. Abdominal pain is emphasized in 71.4% of IBS-C guidelines but not mentioned in functional constipation guidelines 5.
Secondary Causes
Constipation may be secondary to:
- Structural diseases: Stricture, cancer, anal fissure, proctitis
- Metabolic disturbances: Hypercalcemia, hypothyroidism, diabetes mellitus
- Neurologic disorders: Parkinsonism, spinal cord lesions
- Medications: Opiates, anticholinergics, calcium channel blockers 1
Common Pitfall
Not all patients with daily bowel movements are free from constipation—many who report daily movements still describe constipation symptoms due to straining, hard stools, or incomplete evacuation 1. Conversely, reduced stool frequency correlates poorly with delayed colonic transit 1.