Movicol Dosing for Elderly Patients with Constipation
Start with 1 sachet (13.8g) of Movicol once daily, dissolved in 125ml of water, and increase to 2 sachets daily (one in morning, one in evening) if no bowel movement occurs within 3-4 days. 1, 2
Initial Assessment Required
Before starting any oral laxative, perform a digital rectal examination to rule out fecal impaction, as oral laxatives will not work effectively if impaction is present. 2 If impaction is found, manual disimpaction must be performed first, followed by glycerin suppository or isotonic saline enema (never phosphate enemas in elderly due to electrolyte risks), then start maintenance Movicol. 1, 2
Standard Dosing Protocol
Starting dose: 1 sachet (13.8g macrogol/PEG) once daily dissolved in 125ml water. 1, 2 The goal is to achieve one non-forced bowel movement every 1-2 days. 2
Dose escalation if needed after 3-4 days:
- Increase to 2 sachets daily (total 27.6g/day) - one in morning, one in evening. 2
- If still inadequate after another 3-4 days, increase to 3 sachets daily (total 41.4g/day). 2
- Maximum dose for chronic constipation: up to 4 sachets daily can be used. 3
Why Movicol is Preferred for Elderly Patients
Movicol (macrogol/PEG) at 17g/day offers the best efficacy and tolerability in elderly patients with an excellent safety profile. 1 It does not cause electrolyte imbalances, is not absorbed systemically, and is safe even with cardiac and renal comorbidities. 1, 4, 5
Adding Stimulant Laxatives if Needed
If maximum-dose Movicol (3-4 sachets daily) fails after one week, add bisacodyl 10-15mg once daily at bedtime as a stimulant laxative. 2 Alternatively, add senna 2 tablets twice daily. 2, 6
Critical Safety Considerations for Elderly Patients
Avoid these agents entirely in elderly patients:
- Magnesium hydroxide (Milk of Magnesia): Risk of serious hypermagnesemia, especially with any degree of renal impairment. 1, 4, 2
- Bulk-forming laxatives (psyllium, fiber): Increased risk of mechanical obstruction if patient has low fluid intake or is non-ambulatory. 1, 4, 2
- Liquid paraffin: Risk of aspiration lipoid pneumonia if bed-bound or has swallowing difficulties. 1, 2
- Sodium phosphate enemas: Risk of electrolyte disturbances in elderly. 1, 4
Monitor for dehydration and electrolyte imbalances if patient is on diuretics or cardiac glycosides. 1, 4, 6 Regular monitoring is mandatory when combining diuretics with osmotic laxatives. 6
Severe Constipation or Fecal Impaction Dosing
For severe constipation (no bowel movement for 3-4 days) or fecal impaction (no bowel movement for ≥5 days), use higher doses: up to 8 sachets daily (maximum 1 liter/day) divided into 4 doses over 4-6 hours, with 1-1.5 hours between doses, for up to 3 days. 3 This regimen achieved 89% success rate in treating severe constipation and fecal impaction. 3
Non-Pharmacological Measures
Ensure easy toilet access, especially if mobility is limited. 1, 2, 6 Educate patient to attempt defecation twice daily, 30 minutes after meals, straining no more than 5 minutes. 1, 2, 6 Provide dietetic support and manage decreased food intake. 1, 2
Monitoring and Reassessment
Reassess bowel movement frequency after 3-4 days of any dose adjustment. 2, 6 If no improvement after 1 week of escalated therapy, re-examine for impaction or obstruction. 2