RESPONDING TO SYMPTOMS OF MINOR AILMENTS
5) CONSTIPATION
INTRODUCTION
Constipation is defined as infrequent bowel movements (≤2 per week) or difficulty in passing stools, often associated with:
- Hard stools
- Straining
- Pain
- Feeling of incomplete evacuation
Prevalence:
- Elderly: ~20%
- Middle-aged: ~8%
- Young: ~3%
Important:
Constipation is not a disease, but a symptom of
an underlying condition.
Predisposing factors:
- Low-fiber diet
- Inadequate fluid intake
- Physical inactivity
- Disease conditions
- Polypharmacy (multiple drugs)
CAUSES OF CONSTIPATION
1. Gastrointestinal disorders
- Intestinal obstruction (ulcer, cancer)
- Irritable bowel syndrome (IBS)
- Diverticulitis
- Hemorrhoids
- Anal fissures
- Tumors
2. Metabolic & endocrine disorders
- Diabetes mellitus
- Hypothyroidism
- Panhypopituitarism
- Pheochromocytoma
- Hypocalcemia
3. Pregnancy
4. Neurogenic causes
- Head injury
- CNS tumors
- Stroke
- Parkinson’s disease
5. Psychogenic causes
- Psychiatric disorders
- Poor bowel habits
PATHOPHYSIOLOGY
· The GI tract is divided into:
- Upper GI → digestion
- Lower GI → water absorption & stool formation
· Peristalsis moves stool through the intestine
· In constipation:
- Slower transit time
- ↑ Water absorption → hard stool
- ↓ Motility → difficult defecation
Key mechanisms:
- Reduced parasympathetic activity → ↓ motility
- Anticholinergic drugs → slow transit
- Opioids:
- ↑ smooth muscle tone
- ↓ peristalsis
- ↑ sphincter tone
- ↓ rectal sensitivity
→ Leads to severe constipation
MANAGEMENT
General Measures
- Treat underlying disease
- Review and adjust causative drugs
- Lifestyle modification
NON-PHARMACOLOGICAL TREATMENT
- Drink ~2 liters water/day
- Increase dietary fiber (fruits, vegetables, cereals)
- Regular exercise
- Develop regular bowel habits
- Avoid excessive coffee/tea
PHARMACOLOGICAL THERAPY
Types of laxatives based on action
|
Type |
Onset |
Examples |
|
Stool softening (1–3 days) |
Slow |
Bulk laxatives, docusate, lactulose |
|
Soft/semifluid stool (6–12 hrs) |
Moderate |
Senna, bisacodyl |
|
Rapid evacuation (1–6 hrs) |
Fast |
Saline laxatives, castor oil, PEG |
COMMONLY USED AGENTS
1. Bulk-forming laxatives
- First-line in chronic constipation
- Increase stool bulk → stimulate peristalsis
2. Emollient laxatives (Docusate)
- Soften stool by mixing fat & water
- Used for prevention, not treatment
- Useful when straining must be avoided
3. Lubricants (Mineral oil)
- Coat stool → easier passage
- Reduce water absorption
4. Osmotic laxatives
· Lactulose
- Retains water in colon
- Useful in elderly
- Side effects: bloating, cramps
· Sorbitol
- Similar to lactulose
- More economical
5. Saline cathartics
- Examples: Milk of magnesia, magnesium salts
- Rapid action (few hours)
- Use: bowel evacuation (not routine use)
6. Stimulant laxatives
- Senna, Bisacodyl
- Increase intestinal motility
- Used for short-term relief
7. Castor oil
- Strong purgative
- Acts within 1–3 hours
- Not for routine use
8. Glycerin suppositories
- Rectal osmotic action
- Works within 30 minutes
- Safe, especially in children
9. Enemas
- Tap water enema → quick relief
- Used in acute constipation
SPECIAL SITUATIONS
· Acute constipation:
- Enema / glycerin suppository
- Mild laxatives
· Chronic constipation:
- Bulk laxatives first-line
- Lactulose / osmotic agents if needed
· Hospitalized patients:
- Due to anesthesia/opioids
- Use oral/rectal laxatives
WHEN TO REFER TO DOCTOR
- Constipation > 1 week
- Severe abdominal pain
- Blood in stool
- Sudden change in bowel habits
- Elderly patients with new symptoms
