Treatment for 5-Day Constipation
Start polyethylene glycol (PEG) 17g dissolved in 4-8 ounces of water once daily, or alternatively bisacodyl 10-15mg orally 2-3 times daily, after ruling out fecal impaction with a digital rectal exam. 1, 2
Immediate Assessment Required
Before starting any treatment, perform a digital rectal examination to rule out fecal impaction. 2 If impaction is present, you must disimpact first using glycerin suppositories, bisacodyl suppositories, or manual disimpaction before starting maintenance therapy. 3
First-Line Treatment Options
You have two equally effective choices for initial pharmacological management:
Polyethylene glycol (PEG) 17g once daily dissolved in 4-8 ounces of water, juice, soda, coffee, or tea is the American Gastroenterological Association's recommended first-line therapy. 1, 2 This osmotic laxative softens stool by retaining water and typically produces a bowel movement within 2-4 days. 4
Bisacodyl 10-15mg orally 2-3 times daily is equally appropriate as first-line therapy, particularly effective as a stimulant laxative that directly targets colonic motility. 1, 3, 2
Milk of magnesia 1 oz twice daily is an inexpensive alternative osmotic agent with comparable efficacy, costing approximately $1 or less per day. 2
Critical Warnings and Contraindications
Avoid magnesium-containing laxatives (like milk of magnesia or magnesium oxide) if you have any degree of renal insufficiency due to risk of hypermagnesemia. 1, 2
PEG should be used for 2 weeks or less unless directed otherwise, as prolonged use may result in electrolyte imbalance and laxative dependence. 4
Common side effects of PEG include abdominal distension, loose stool, flatulence, and nausea. 1
If First-Line Treatment Fails After 3-5 Days
Add a second agent from a different class rather than increasing the dose of your initial choice:
- Add senna or bisacodyl (if you started with PEG) 2
- Add lactulose, magnesium hydroxide, or magnesium citrate (if you started with bisacodyl) 2
- Consider rectal bisacodyl suppository once daily for more rapid effect 2
What NOT to Do
Do not add stool softeners like docusate to your regimen - evidence shows they provide no additional benefit when combined with stimulant laxatives. 2
Do not rely on fiber supplements alone - psyllium and other fibers are ineffective for acute constipation and require adequate hydration (at least 2 liters daily) to work. 2, 5 Fiber is only appropriate as maintenance therapy for individuals with chronically low dietary fiber intake. 1
Do not use metoclopramide unless gastroparesis is suspected - it primarily affects the upper GI tract and has little effect on colonic motility. 3
Treatment Goal
Aim for one non-forced bowel movement every 1-2 days, not necessarily daily bowel movements. 3, 2 This is the evidence-based target that balances symptom relief with avoiding overtreatment.
When to Seek Further Evaluation
If constipation persists beyond 2 weeks despite appropriate laxative therapy, you need assessment for: