Medication Management for Postpartum Urinary Retention and Constipation
For postpartum urinary retention, no medications are recommended—instead, use bladder catheterization with clean intermittent self-catheterization until spontaneous voiding returns, while for constipation, start with bulk-forming agents or stool softeners, escalating to osmotic laxatives (polyethylene glycol, lactulose) or stimulant laxatives (bisacodyl, senna) only for short-term use.
Urinary Retention Management
Non-Pharmacologic Approach (First-Line)
- Bladder catheterization is the primary treatment for postpartum urinary retention, not medications 1, 2
- Insert a Foley catheter immediately if the patient cannot void, particularly after perineal trauma repair 3
- Perform a voiding trial on postpartum day 1 to assess bladder function 3
- If retention persists, teach clean intermittent self-catheterization and measure post-void residual volumes every 2 days until day 15, then at 6,12,24, and 36 months 2
- Most cases resolve by day 7, though 8.2% may have voiding disorders at 1 year and 4.9% at 3 years 2
Why Medications Are Not Recommended
- No pharmacologic agents are effective for stress urinary incontinence or urinary retention 3, 4
- Antimuscarinic medications (used for urgency incontinence) can paradoxically worsen urinary retention and cause constipation 3, 5
- The underlying pathophysiology is detrusor muscle overdistension injury and parasympathetic nerve damage, which requires time to heal, not medication 1, 2
Risk Factor Awareness
- Operative vaginal deliveries account for 89% of postpartum urinary retention cases 2
- Other risk factors include prolonged second stage of labor, episiotomy, perineal lacerations, and macrosomic infants (>4000g) 6, 7
Constipation Management
First-Line Medications (Safe During Lactation)
- Bulk-forming agents (psyllium, methylcellulose): minimal systemic absorption, safe during breastfeeding 8
- Stool softeners (docusate): 2-3 tablets twice to three times daily, safe with minimal absorption 3, 8
Second-Line Medications (Short-Term Use Only)
Important Caveats for Lactating Women
- Avoid diuretics (furosemide, hydrochlorothiazide, spironolactone) as they may reduce milk production 3
- Use osmotic and stimulant laxatives only short-term or occasionally to prevent dehydration and electrolyte imbalances 8
- Increase fluids and dietary fiber first if the patient has adequate fluid intake 3
Medications to Avoid
- Do not use antimuscarinic medications (oxybutynin, tolterodine, solifenacin) for urinary retention, as they cause constipation and urinary retention as side effects 3, 5
- Methyldopa (sometimes used for postpartum hypertension) should be used cautiously in women at risk for depression 3
Antihypertensive Medications Compatible with Breastfeeding (If Needed)
If the patient has postpartum hypertension requiring treatment, the following are safe during lactation 3:
- ACE inhibitors: enalapril, captopril, benazepril (unless neonate is premature or has renal failure) 3
- Calcium channel blockers: nifedipine, diltiazem, verapamil 3
- Beta-blockers: labetalol, metoprolol, propranolol 3
Key Clinical Pitfalls
- Never prescribe anticholinergic/antimuscarinic medications for a postpartum patient with urinary retention—they will worsen both retention and constipation 3, 5
- Monitor for bladder overdistension, which can lead to permanent detrusor atony if left untreated beyond 6 hours 1, 6
- Recognize that covert urinary retention (incomplete emptying) is often missed—measure post-void residual if the patient has risk factors 1, 6
- Osmotic and stimulant laxatives should not be used long-term in lactating women due to risk of dehydration and electrolyte disturbances 8