Hard stool

Firm fecal matter that is dry, overconcentrated, and difficult or painful to evacuate, typically resulting from prolonged colonic transit and increased water absorption from stool.

Causes

• Lifestyle and dietary causes

  • Dehydration

  • Low-fiber diet: Lack of fruits, vegetables and whole grains

  • Physical inactivity

  • Suppressing or delaying bowel movements

• Medication-related causes

  • Opioids

  • Antidepressants

  • Iron supplements

  • Antacids

  • Calcium channel blockers

• Functional gastrointestinal disorders

  • Irritable bowel syndrome with constipation

  • Slow-transit constipation

  • Pelvic floor dysfunction

• Colorectal obstruction

• Endocrine and metabolic causes

  • Hypothyroidism

  • Diabetes mellitus

  • Electrolyte disturbances

• Neurological causes

  • Parkinson's disease

  • Multiple sclerosis

  • Spinal cord injury

  • Autonomic nerve dysfunction affecting bowel motility

• Physiological and other causes

  • Pregnancy

  • Aging-related changes in bowel motility