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Urinary Frequency


Geetha Maddukuri

, MD, Saint Louis University

Last full review/revision Jan 2021| Content last modified Jan 2021
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Urinary frequency is the need to urinate many times during the day, at night (nocturia), or both but in normal or less-than-normal volumes. Frequency may be accompanied by a sensation of an urgent need to void (urinary urgency). Urinary frequency is distinguished from polyuria, which is urine output of >3 L/day.

Pathophysiology of Urinary Frequency

Urinary frequency usually results from disorders of the lower genitourinary tract. Inflammation of the bladder, urethra, or both causes a sensation of the need to urinate. However, this sensation is not relieved by emptying the bladder, so once the bladder is emptied, patients continue trying to void but pass only small volumes of urine.

Etiology of Urinary Frequency

There are many causes of urinary frequency (see table Some Causes of Urinary Frequency), but the most common include


Some Causes of Urinary Frequency


Suggestive Findings

Diagnostic Approach

Progressive onset of urinary hesitancy, incontinence, poor urine stream, a sensation of incomplete voiding

Rectal examination



Urinary incontinence

Sensation of vaginal fullness

Pain or urinary leakage during sexual intercourse

Pelvic examination

Drugs and substances

  • Caffeine

  • Alcohol

  • Diuretics

Urinary frequency in an otherwise healthy patient

Empiric elimination of offending substance (to confirm that frequency resolves)


3rd trimester of pregnancy

Clinical evaluation

Urgency, dysuria, nocturia, purulent urethral discharge with fever, chills, low back pain, myalgia, arthralgia, and perineal fullness

Prostate tender to palpation

Rectal examination

Culture of secretions after prostatic massage

Radiation cystitis

History of radiation therapy of the lower abdomen, prostate, or perineum for treatment of cancer

Clinical evaluation

Asymmetric arthritis of knees, ankles, and metatarsophalangeal joints

Unilateral or bilateral conjunctivitis

Small, painless ulcers on the mouth, tongue, glans penis, palms, and soles 1–2 weeks after sexual contact

STD testing

Lower-extremity weakness, decreased anal sphincter tone, absent anal wink reflex

Loss of sensation at a segmental level

Injury usually clinically obvious

MRI of the spine

Hesitancy, tenesmus, reduced caliber and force of the urine stream


Unintentional passage of urine, particularly when bending, coughing, or sneezing


Colicky flank or groin pain

Urinalysis for hematuria

Ultrasonography or CT of the kidneys, ureters, and bladder

Dysuria and foul-smelling urine, sometimes fever, confusion, and flank pain, particularly in women and girls

Dysuria and frequency in young sexually active men (which suggests an STD)

Urinalysis and culture

STD testing

Bladder detrusor overactivity

Nocturia, urge incontinence, weak urinary stream, and sometimes urinary retention


STD = sexually transmitted disease.

Evaluation of Urinary Frequency


History of present illness should first ask about the amounts of fluid consumed and voided to distinguish between urinary frequency and polyuria. If urinary frequency is present, patients are asked about acuity of onset, presence or absence of irritative symptoms (eg, irritation, urgency, dysuria), obstructive symptoms (eg, hesitancy, poor flow, sensation of incomplete voiding, nocturia), and recent sexual contacts.

Review of systems should cover symptoms suggestive of a cause, including fever, flank or groin pain, and hematuria (infection); missed menses, breast swelling, and morning sickness (pregnancy); and arthritis and conjunctivitis (reactive arthritis).

Past medical history should ask about known causes, including prostate disease and previous pelvic radiation therapy or surgeries. Drugs and diet are reviewed for the use of agents that increase urine output (eg, diuretics, alcohol, caffeinated beverages).

Physical examination

Examination focuses on the genitourinary system.

Any urethral discharge or any lesions consistent with sexually transmitted diseases are noted. Rectal examination in men should note the size and consistency of the prostate and rectal tone; pelvic examination in women should note the presence of any cystocele. Patients should be instructed to cough while the urethra is observed for signs of urinary leakage.

The costovertebral angle should be palpated for tenderness, and the abdominal examination should note the presence of any masses or suprapubic tenderness.

Neurologic examination should test for lower-extremity weakness and loss of sensation.

Red flags

The following findings are of particular concern:

  • Lower-extremity weakness or signs of spinal cord damage (eg, loss of sensation at a segmental level, loss of anal sphincter tone and anal wink reflex)

  • Fever and back pain

Interpretation of findings

Dysuria suggests frequency is due to urinary tract infection (UTI) or calculi. Prior pelvic surgery suggests incontinence. Weak urine stream, nocturia, or both suggests benign prostatic hyperplasia (BPH). Urinary frequency in an otherwise healthy young patient may be due to excessive intake of alcohol or caffeinated beverages. Gross hematuria suggests UTI and calculi in younger patients and genitourinary cancer in older patients.


All patients require urinalysis and culture, which are easily done and can detect infection and hematuria.

Cytoscopy, cystometry, and urethrography can be done to diagnose cystitis, bladder outlet obstruction, and cystocele. Prostate-specific antigen level determination, ultrasonography, and prostate biopsy may be required, especially in older men, to differentiate BPH from prostate cancer.

Treatment of Urinary Frequency

Treatment varies by cause.

Geriatrics Essentials

Urinary frequency in older men is often caused by bladder neck obstruction secondary to prostate enlargement or cancer. These patients usually require postvoid residual urine volume determination. Urinary tract infection or use of diuretics may be a cause in both sexes.

Key Points

  • UTI is the most common cause in children and women.

  • Prostate disease is a common cause in men aged > 50 years.

  • Excessive intake of caffeine can cause urinary frequency in healthy people.

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