Gabapentin Can Cause Urinary Incontinence
Yes, gabapentin can cause urinary incontinence, though this is an uncommon adverse effect that is not listed in the FDA drug label but is well-documented in case reports and pharmacovigilance data. This side effect typically manifests as overflow incontinence and usually occurs within days to weeks of starting the medication 1, 2, 3.
Evidence from Clinical Reports
Multiple case reports demonstrate a clear causal relationship between gabapentin and urinary incontinence:
Rechallenge-confirmed cases: A 2019 case report documented urinary incontinence that resolved upon gabapentin discontinuation, recurred with rechallenge, and resolved again upon stopping the drug—providing the strongest evidence of causation 2.
Temporal relationship: Incontinence typically develops within 1-10 days of starting gabapentin, with resolution occurring within 1-7 days after discontinuation 3.
Dose-dependent effect: One case showed overflow incontinence at 1200 mg/day that resolved when self-tapered to 600 mg/day, though pain control was inadequate at the lower dose 1.
Pharmacovigilance Data
A 2025 analysis of the FDA Adverse Event Reporting System (FAERS) identified gabapentin among neuropsychiatric drugs associated with drug-induced urinary incontinence, with over half (57.12%) of cases occurring within 30 days of medication initiation 4.
Clinical Characteristics
The incontinence pattern is typically:
- Overflow type rather than stress or urgency incontinence
- Occurs without dysuria or urgency
- Not worsened by movement, coughing, sneezing, or laughing
- Presents as intermittent episodes throughout the day
Important Caveats
The FDA drug label does not list urinary incontinence as an adverse effect 5. The label mentions impotence (2% vs 1% placebo) in the urogenital system category but does not reference incontinence. This represents an underrecognized adverse effect in official labeling despite documented case reports.
Clinical Management Algorithm
When evaluating new-onset urinary incontinence in a patient taking gabapentin:
Assess temporal relationship: Did incontinence begin within days to weeks of starting gabapentin or increasing the dose?
Rule out other causes: Perform urinalysis to exclude infection; assess for anatomical causes if indicated by history
Consider gabapentin discontinuation or dose reduction: If temporal relationship is clear and no other cause is identified
Monitor for resolution: Incontinence should resolve within 1-7 days if gabapentin is the cause
Consider alternative agents: If gabapentin must be continued for pain control, pregabalin may be an option—one case report showed successful pain control with pregabalin without recurrence of incontinence 1
Quality of Life Impact
While not life-threatening, gabapentin-induced incontinence can be profoundly embarrassing and lead to medication non-adherence 2. Patients should be counseled about this potential side effect when initiating therapy, particularly older adults who may be at higher risk 3.
Patient Populations at Risk
The reported cases primarily involve:
- Adults aged 56-66 years with neuropathic pain 3
- Patients receiving doses of 600-1200 mg/day
- Both male and female patients