Overflow Incontinence: Causes, Symptoms, Diagnosis, and Treatment

TL;DR

Overflow incontinence happens when the bladder doesn’t empty completely (urinary retention). As urine builds up, the bladder becomes overfull and you may leak or dribble urine. Common causes include bladder outlet obstruction (e.g., enlarged prostate, pelvic organ prolapse) and weak/underactive bladder muscle or nerve problems (e.g., diabetes, spinal cord or neurologic conditions), sometimes worsened by medications. Diagnosis often includes measuring postvoid residual (PVR) urine with ultrasound. Treatment focuses on fixing the cause and may include bladder habits, medication changes, alpha-blockers (for prostate-related obstruction), catheterization, or procedures/surgery to relieve blockage.

Medical note: This article is educational and not a substitute for medical care. If you suspect urinary retention or have new/worsening symptoms, contact a clinician.

What is overflow incontinence?

Overflow incontinence is urine leakage caused by a bladder that’s too full because it can’t empty all the way. When urine stays in the bladder (urinary retention), pressure builds until urine leaks out—often as dribbling.

Key facts

• Overflow incontinence is less common than stress or urge incontinence—about 5% of chronic urinary incontinence.
• It’s important to identify because chronic poor emptying can lead to complications, including kidney problems.

Why overflow incontinence happens: the two main mechanisms

Overflow incontinence typically results from one (or both) of the following:

1. Bladder outlet obstruction (blockage)
• Urine can’t flow out normally, so the bladder retains urine and overfills.
2. Detrusor underactivity (weak bladder squeeze) / nerve signaling issues
• The bladder muscle doesn’t contract strongly or consistently enough to empty fully.

Common causes and risk factors

Outlet obstruction (blockage)

• Enlarged prostate (BPH) is a common cause in people with prostates.
• Pelvic organ prolapse (e.g., bladder or uterine prolapse) can contribute in people with a vagina.
• Scar tissue/urethral stricture after prostate surgery, urethral surgery, or radiation.

Nerve or muscle causes

• Diabetes, spinal cord injury, multiple sclerosis, and other neurologic conditions can disrupt bladder control signals.

Medication-related urinary retention

Some drugs can reduce bladder contractions or worsen retention (examples include certain anticholinergics/antihistamines, opioids, sedatives, some antidepressants/antipsychotics, and others). A clinician review of your meds is a key step.

Symptoms of overflow incontinence

Overflow incontinence often looks like “leaking + trouble emptying,” such as:

• Frequent dribbling or constant leakage
• Difficulty starting urination (hesitancy)
• Weak stream or start-stop flow
• Straining to urinate
• Feeling incomplete emptying or “still need to go”
• Nighttime leakage or repeated nighttime urination may occur (often due to ongoing retention/overfilling).

How clinicians diagnose overflow incontinence

A typical evaluation may include:

• History + medication review (new meds matter)
• Physical exam (may include pelvic exam or prostate/rectal exam)
• Urinalysis (check for infection/blood)
• Postvoid residual (PVR) measurement: how much urine remains after you urinate
• Often done via bladder ultrasound; sometimes via in-and-out catheter.
• Overflow incontinence usually doesn’t occur unless emptying is poor (commonly cited thresholds: PVR > 200–300 mL).
• If needed: cystoscopy, imaging, or urodynamic testing, especially when the cause isn’t clear.

Treatment and management options

Treatment depends on why the bladder isn’t emptying. Common approaches include:

1) Behavior and “bladder mechanics”

• Timed voiding (regular bathroom schedule) to reduce overfilling
• Double voiding (go, wait a minute, try again) to improve emptying
• Fluid pacing (avoid chugging large amounts at once)
• Address constipation (it can worsen bladder emptying)

2) Medication changes

• If a medication is contributing to retention, a clinician may adjust it.

3) Medications for prostate-related obstruction

• If an enlarged prostate is contributing, clinicians may use alpha-blockers (examples include tamsulosin, terazosin, etc.).

4) Catheterization

• If the bladder can’t empty adequately, catheterization (intermittent or short-term/long-term depending on situation) may be recommended.

5) Procedures or surgery

• When an anatomic blockage is the root cause, procedures to relieve obstruction may be considered.

Practical products for day-to-day leak management

While you and your clinician work on the underlying cause, supportive products can reduce stress and protect skin and surfaces:

• Absorbent pads/briefs/underwear (choose absorbency based on your leak volume)
• Furniture/bed underpads to protect mattresses and chairs
• Bedside urinal options for people with limited mobility or high nighttime risk

When to seek medical care urgently

Schedule care promptly—especially if you have:

• Inability to urinate at all, severe lower abdominal pain/pressure
• Weak stream + worsening retention symptoms
• Fever/chills, blood in urine, or new back/lower abdominal pain (possible infection/complications)

Key takeaways

• Overflow incontinence = leakage from an overfull bladder due to incomplete emptying.
• It’s relatively uncommon (~5% of chronic incontinence) but important to identify because retention can cause complications.
• Diagnosis often includes measuring postvoid residual (PVR) urine.
• Treatment targets the cause (obstruction vs weak bladder/nerve issues) and may include habit changes, medication adjustments, alpha-blockers, catheterization, or procedures/surgery.

FAQs

Can lifestyle changes alone fix overflow incontinence?
Sometimes they help—especially fluid pacing, timed voiding, and addressing constipation—but many cases require treating an underlying cause like obstruction or retention.

How is overflow incontinence different from urge incontinence?
Urge incontinence usually involves a sudden urge and leakage due to bladder overactivity. Overflow incontinence is leakage from retention (too-full bladder).

What test most directly supports an overflow incontinence diagnosis?
A postvoid residual (PVR) measurement (often ultrasound) helps show incomplete emptying.