Double voiding is a bladder-emptying technique used to help fully empty the bladder and reduce residual urine.
After urinating normally, you wait 20–30 seconds, then lean forward slightly, or stand up and sit back down, relax, and try to urinate again.
The second void helps expel urine that remained in the bladder.
Sometimes the bladder doesn’t fully contract and empty in one go, leaving residual urine behind.
This is a common symptom of incomplete bladder emptying and can result from various causes affecting bladder function or outlet obstruction.
This can be due to an overactive or underactive bladder, pelvic floor dysfunction, an enlarged prostate, or simply habit.
Double voiding is recommended for:
People with urinary retention or incomplete bladder emptying Men with benign prostatic hyperplasia (BPH) Women with pelvic organ prolapse People with neurogenic bladder (e.g., from diabetes, MS, or spinal cord issues) Those with recurrent urinary tract infections (UTIs), since residual urine can harbor bacteria
Benefits of double voiding:
Reduces risk of UTIs Decreases urinary urgency and frequency Helps prevent overflow incontinence Can reduce post-void dribbling
Benign prostatic hyperplasia (BPH) is the most common cause in men over 50, affecting up to 40% of this population.
BPH causes bladder outlet obstruction through both static/mechanical blockage from prostate enlargement and dynamic with increased smooth muscle tone mechanisms, leading to incomplete emptying and the need for double voiding.
Men with BPH typically report weak stream, hesitancy, intermittency, and post-void dribbling in addition to double voiding.
Detrusor underactivity results from impaired bladder muscle contractility, often due to chronic bladder outlet obstruction, aging, or diabetes.
The weakened detrusor cannot generate sufficient pressure to completely empty the bladder, necessitating a second void.
Overactive bladder (OAB) affects approximately 16% of men and 27% report lower urinary tract symptoms consistent with OAB.
OAB primarily causes urgency and frequency, and can coexist with incomplete emptying, particularly when detrusor overactivity is followed by poor contractility.
Bladder diverticulum can trap urine that empties slowly after the initial void, creating a sensation of incomplete emptying and prompting double voiding.
Large diverticula may hold significant residual volumes.
Urethral stricture should be considered, particularly in men with history of urethral instrumentation, catheterization, sexually transmitted infections, or trauma.
Strictures cause decreased urinary stream, incomplete emptying, and dysuria.
Bladder cancer can present with obstructive voiding symptoms, particularly when tumors are located at the bladder neck or involve significant portions of the bladder wall.
Any patient with microscopic or gross hematuria accompanying double voiding requires urgent evaluation.
Prostate cancer causing significant outlet obstruction is less common than BPH but must be considered, especially with abnormal digital rectal examination findings or elevated PSA.
Cauda equina syndrome presents with urinary retention, bilateral lower extremity weakness or numbness, saddle anesthesia, and bowel dysfunction.
Post-void residual >500 mL combined with bilateral sciatica and subjective urinary retention significantly increases likelihood.
Neurogenic bladder from spinal cord injury, multiple sclerosis, diabetes, or other neurologic conditions can cause incomplete emptying.
History of neurologic disease, progressive symptoms, or associated neurologic deficits should prompt consideration.
Diagnosis:
Determining onset and duration of symptoms, association with lower urinary tract symptoms (urgency, frequency, nocturia, weak stream, hesitancy), history of neurologic disease or diabetes, prior urologic procedures or infections, medications (anticholinergics, decongestants, opioids can worsen retention), and presence of hematuria or constitutional symptoms.
Examination: Palpate lower abdomen for bladder distention, perform digital rectal exam to assess prostate size and consistency, although size correlates poorly with actual prostate volume, and conduct focused neurologic exam including perineal sensation, lower extremity strength and reflexes, and anal tone if neurogenic bladder suspected.
Workup:
Post-void residual (PVR) measurement via bladder ultrasound is essential; PVR >300 mL indicates significant retention.
Urinalysis and urine culture to exclude infection.
Voiding diary (24-72 hours) to document voiding frequency, volumes, and fluid intake patterns.
Uroflowmetry if available, which can detect low flow rates and abnormal voiding patterns.
Serum PSA if age >50 and concern for prostate pathology.
Basic metabolic panel and glucose if diabetes or renal insufficiency suspected.
Immediate urology referral for gross hematuria (cancer risk 10-25%), PVR >500 mL, acute urinary retention, new neurologic symptoms suggesting cauda equina (saddle anesthesia, bilateral leg weakness, bowel dysfunction), or refractory symptoms despite initial management.
Consider MRI of spine if any concern for cauda equina syndrome, as PVR >200 mL with objective neurologic signs has 43% probability of cauda compression.