Doctor's Notes on Inability to Urinate
An inability to urinate means that person cannot pass urine out of the body through the urethra. Another broad term for inability to urinate is urinary retention, although urinary retention may be considered as either partial or complete. This is different from anuria, which means the person’s body is not producing urine in the kidneys, because people that cannot acutely urinate still produce urine.
There are two types of urinary retention, acute and chronic. Acute may occur suddenly and chronic may occur over a longer timespan. Acute obstruction is a medical emergency and can be life threatening. The causes of the inability to urinate can be either obstruction of the urethra or non-obstruction of the urethra but are due to muscle and/or nerve problems that interfere with normal signals between your brain and your bladder. The inability to urinate is a symptom itself of underlying medical problems that may affect the urinary tract.
Obstructive urinary retention or the inability to urinate are due to underlying causes. The causes include the following and frequently involve putting pressure on the urethra or obstruction of the urethral lumen that results in little or no ability for urine to pass out of the body.
- enlarged prostate in men (BPH or benign prostatic hypertrophy),
- tumors and/or cancers,
- urethral strictures,
- cystocele (prolapse bladder),
- rectocele (prolapse of the wall between the rectum and the vagina),
- constipation, and
- kidney or bladder stones.
Non-obstructive urinary retention or the inability to urinate are also due to underlying causes that alter the body’s nerves and/or musculature involved in urination include the following:
- pelvic injury or trauma,
- accidents that cause injury to the brain and/or spinal cord,
- medications and/or anesthesia that results in impaired muscle or nerve function,
- nerve disease, and
- vaginal childbirth.
What are the signs and symptoms of a person’s inability to urinate?
Symptoms and signs differ between acute and chronic urinary retention. Acute urinary retention symptoms need to be treated emergently as they can further develop into life-threatening conditions (for example, bladder rupture, sepsis). The following symptoms need emergent medical attention:
- an acute inability to urinate,
- urgent and painful feeling or need to urinate, and
- severe pain in the lower abdomen.
Chronic urinary retention symptoms may include the following:
- urinary frequency (about 8 or more times per day)
- urgent need to urinate with little success in urination
- difficulty beginning a urine stream
- weak or interruptions urine stream
- feeling that you need to urinate even after you just finished urination
- urge incontinence (uncontrollable urge to frequently urinate; may develop bed-wetting)
- difficulty emptying your bladder
- relatively constant mild to moderate discomfort in the lower abdomen and/or urinary tract
- straining to empty your bladder
- nocturia (waking up 2 or more times per night to urinate)
In some individuals, chronic urinary retention may lead to an acute episode of urinary retention; if this occurs, it is a medical emergency.
Complications that may occur with acute and/or chronic urinary retention include the following:
- Urinary tract infections
- Kidney damage
- Bladder damage
Inability to Urinate Symptoms
With urinary retention, there is an inability to urinate or completely empty the bladder despite an urge to urinate. Some people have the following symptoms:
- Most people with acute urinary retention also feel pain in the lower abdomen (pelvis) along with the inability to urinate. Chronic urinary retention is usually painless.
- With acute and chronic urinary retention, a full bladder can often be felt just above the pubic bone and may extend to the belly button (umbilicus). Tapping on the lower abdomen will elicit a hollow sound.
- A small amount of urine may leak out of the bladder but generally not enough to relieve symptoms and the urine stream is often described as being very weak, like a dribble.
- There may be constant leakage of urine, known as urinary incontinence.
- Chronic urinary retention may be associated with decreased urine stream, feeling of incomplete bladder emptying, and/or straining to urinate.
- Back pain, fever, and painful urination may indicate a urinary tract infection.
Inability to Urinate Causes
There are a number of medical conditions and medications that may cause urinary retention. These medical conditions and medications may affect the function of the bladder itself, the function of the outlet of the bladder, and/or the urethra. Obstruction may be fixed (due to a mass blocking the bladder outlet) or dynamic (lack of coordination between the bladder and the muscles surrounding the bladder outlet and urethra). There are also infectious causes and surgical causes of urinary retention.
Common Causes/Risk Factors
- Blockage (obstruction): The most common cause of blockage of the urethra in men is enlargement of the prostate. In males, the prostate gland surrounds the urethra. If the prostate becomes enlarged, which is common in older men, it may compress the urethra, causing resistance/blockage to the outflow of urine. The most common cause of prostate enlargement is benign prostatic hypertrophy (often called BPH). Other causes of prostate enlargement include prostate cancer. Acute infection of the prostate (prostatitis) may cause swelling of the prostate and lead to urinary retention. Less common obstructive causes in men include meatal stenosis (narrowing of the opening at the tip of the penis that urine passes through, which may be the result of chronic irritation or prior hypospadias surgery), paraphimosis (in which the foreskin in an uncircumcised male retracts and cannot be pulled back down, resulting in swelling and constriction), penile constricting bands, and penile cancer. Other causes of blockage of the urethra that can occur in both males and females include scar tissue in the urethra from prior trauma, surgery or infection (urethral stricture), injury to the bladder outlet or urethra (as in a car accident or bad fall), blood clots due to bladder infection or trauma, tumors in the bladder or pelvic region, severe constipation, and bladder or urethral stones or foreign bodies in the bladder or urethra. Blockage to the outflow of urine may also be due to lack of coordination between the bladder and the bladder outlet, bladder neck dysfunction, and/or lack of coordination between the bladder and the muscles surrounding the urethra, known as bladder-sphincter dysfunction. Bladder-sphincter dysfunction may be voluntary or involuntary. Voluntary bladder-sphincter dysfunction is seen in individuals who chronically hold their urine and tighten the pelvic floor muscles/sphincter when an urge to urinate occurs. Chronic tightening of these muscles leads to an inability to properly relax the muscles when urinating. Involuntary relaxation of the pelvic floor muscles/sphincter muscles occurs in individuals with neurologic conditions that can affect bladder and sphincter function. Lastly, in women, obstruction to the outflow of urine may be due to a large cystocele, or herniation of the bladder into the vagina, or may be the result of surgeries to treat urinary incontinence, such as sling procedures.
- Nerve problems: Disruption of the nerves between the bladder and the brain can cause you to lose control of your bladder function. The problem may lie in the nerves that send messages back and forth or in the nerves that control the muscles used in urination, or both. Individuals who suffer from such conditions are referred to as having a "neurogenic bladder." Occasionally, urinary retention is the first sign of spinal cord compression, a medical emergency that must be treated right away to prevent permanent, serious disability. The most common causes of this disruption include spinal cord injury, spinal cord tumor, strokes, diabetes mellitus, herniated or ruptured disk in the vertebral column of the back, or an infection or blood clot that places pressure on your spinal cord, and congenital spinal cord problems such as myelomeningocele (spina bifida) and tethered spinal cord. Nerve problems can also affect the ability of the muscles around the urethra to relax during urination, known as detrusor sphincter dyssynergia (DSD), which can lead to urinary retention.
- Infection and inflammation: In males, inflammation of the head of the penis, the glans (balanitis), and infection of the prostate (prostatitis) or an abscess of the prostate may result in urinary retention. In women, infection of the vulva and vagina, vulvovaginitis, as well as chronic inflammation and resultant scarring, lichen sclerosus, may cause urinary retention. In both males and females, bladder infections, Guillain-Barré syndrome, Lyme disease, periurethral abscess, transverse myelitis, tuberculosis affecting the bladder, infection of the urethra (urethritis), and herpes zoster (shingles) can cause urinary retention. Herpes simplex virus can cause pain in the perineum and affect the nerves leading to urinary retention. Infections around the spinal cord can cause retention by placing pressure on the nerves of the spinal cord.
- Trauma to the pelvis, penis, and perineum can cause urinary retention. Fractures of the pelvis can cause damage to the bladder outlet and urethra, and the healing of such injuries can lead to obstruction from scar tissue.
- Surgery: Urinary retention is a relatively common problem after surgery. It can be a direct result of the anesthetic or the type of operation. Relative immobility after a surgery can also contribute to urinary retention. Previous bladder or prostate surgeries can sometimes cause urinary retention because of the formation of strictures (narrowing) due to scar tissue. This can occur after prostate cancer surgery (radical prostatectomy) as well as surgery for benign prostate enlargement (BPH) (transurethral prostatectomy, laser prostatectomy, and cryotherapy).
- Chronic overdistention of the bladder (holding one's urine for long periods of time) or excess alcohol intake can lead to urinary retention.
- Immobility may result in urinary retention.
- Other causes of transient urinary retention include immobility (especially post-operative), constipation, delirium, endocrine (hormone) problems, psychological problems, and prior instrumentation (medical procedures involving placing instruments in the urethra) of the urethra.
Certain medications can cause urinary retention, especially in men with prostate enlargement. Many of these medications are found in over-the-counter cold and allergy preparations. These drugs include the following:
- Drugs that act to tighten the urinary channel and block the flow of urine include ephedrine (Kondon's Nasal, Pretz-D), pseudoephedrine (Actifed, Afrin, Drixoral, Sudafed, Triaminic), phenylpropanolamine (Acutrim, Dexatrim, Phenoxine, Prolamine), phenyleprhine (neosynephrine), and amphetamines.
- Antihistamines such as diphenhydramine (Benadryl, Compoz, Nytol, Sominex) and chlorpheniramine (Chlor-Trimeton, Allergy 8 Hr), as well as some older antidepressants, can relax the bladder too much and cause urination problems.
- Anticholinergics, medications commonly used to treat overactive bladder, as well as other conditions such as oxybutynin (Ditropan, Ditropan XL, oxytrol), tolterodine (detrol, detrol LA), darifenacin (Enablex), solifenacin (VESIcare), trospium chloride (Sanctura, Sanctura XR), atropine, belladone and opioid, dicyclomine (Bentyl), flavoxate (Urispas), glycopyrrolate (Robinul), hyoscyamine (Levsin), propantheline (Pro-Banthine), and scopolamine (transdermal scopolamine)
- Certain antidepressants may affect bladder/sphincter function, including amitriptyline (Elavil), amoxapine, doxepin, imipramine (Tofranil), and nortriptyline (Pamelor).
- Cox-2 inhibitors, used for treating such conditions as sports injuries, arthritis, colorectal polyps, and menstrual cramps
- Some medications used to treat heart arrhythmias may affect urination, including disopyramide (Norpace), procainamide (Pronestyl), and quinidine.
- Certain antihypertensive medications, including hydralazine and nifedipine (Procardia)
- Antiparkinsonian medications, including amantadine (Symmetrel), benztropine (Cogentin), bromocriptine (Parlodel), and levodopa
- Antipsychotics, including chlorpromazine (Thorazine), fluphenazine, haloperidol (Haldol), prochlorperazine (Compazine), thioridazine (Mellaril), and thiothixene (Navane).
- Muscle relaxants, including baclofen (Lioresal), cyclobenzaprine (Flexeril), and diazepam (valium)
- Beta-adrenergic sympathomimetics, including isoproterenol (Isuprel), terbutaline (Brethine), and metaproterenol (Alupent)
- Opioid-containing medications
Urinary Retention in Children
- A child can have problems from birth that cause an inability to urinate properly. These problems may be identified prenatally. Such conditions include posterior and anterior urethral valves (areas of obstruction in the male urethra), ureterocele (a dilation of the part of the ureter that is within the bladder), and neurologic conditions such as myelomeningocele (spina bifida) and tethered cord. Children may develop urinary retention as a result of scarring from trauma to the urethra (straddle injury, pelvic trauma, or prior urethral instrumentation) and surgical procedures such as hypospadias procedures and continence procedures.
- A child may suddenly become unwilling to urinate. This is generally due to a temporary condition that is causing pain with urination. Pain can be caused by a vaginal yeast infection in girls or an irritation from soap or shampoo used in bathing. Almost always, the child will eventually urinate without further help. Chronic holding of urine and failing to relax the pelvic floor muscles with voiding (dysfunctional voiding) may result in urinary retention.
- Severe constipation may result in urinary retention.
- A history of sexual abuse also is associated with urinary retention.
Medical evaluation for urinary retention includes a medical and physical examination (including a prostate examination in men) as well as laboratory tests (if indicated) to find the cause of the problem.
On physical examination, the bladder may be visible and/or palpable (be felt by the examiner). A rectal examination in a male may demonstrate an enlarged prostate, an enlarged prostate with hard areas suspicious for prostate cancer, or prostate tenderness suggestive of prostatitis. A penile examination can identify abnormalities of the penile skin and the meatus, the opening at the tip of the penis that urine passes through, or signs of prior penile surgery such as prior hypospadias repair. Examination of the genitalia in a female may demonstrate a large cystocele (prolapse of the bladder into the vagina). A rectal examination in both males and females may reveal fecal impaction.
A bladder scan (portable ultrasound-like evaluation) is often used to determine how much urine is in the bladder to confirm the diagnosis of urinary retention.
A renal (kidney) and bladder ultrasound may be helpful to determine if there is hydronephrosis (a backup of urine in the kidneys) or bladder stones.
A pelvic ultrasound or CT of the abdomen/pelvis may be indicated to check for pelvic, abdominal, or retroperitoneal conditions.
A catheter can be placed in the urethra. This is a thin, flexible tube. It goes up the bladder and drains the urine into a bag.
- This is done both for diagnosis and as a treatment of the immediate problem. Draining urine almost always relieves the symptoms, at least for a while.
- A urine sample will be taken to check for signs of infection, bladder irritation, stones, or other problems.
Other lab tests may be done, depending on your doctor's conclusions from your medical interview and exam.
- Blood may be drawn to check for signs of infection, to check your kidney function, and levels of certain chemicals in your blood that may be altered if your kidneys are not working well, and possibly to rule out certain conditions.
- The blood also may be checked for prostate-specific antigen (PSA). This is the same test used to screen men for prostate cancer.
- A sample of the secretions from your penis (men) or vagina (women) may be checked for signs of infection as well.
People with chronic urinary retention or suspected bladder muscle weakness may be referred to a specialist in disorders of the urinary tract (urologist or urogynecologist).
- The urologist may perform advanced urodynamic testing to see what is causing the problem. A urodynamic test is a specialized test used to determine bladder and urethral function. This study involves the placement of a catheter in the urethra, a separate small catheter in the rectum, and electrode patches on the outside area around the urethra and rectum. The bladder is filled with sterile fluid, and pressures within the bladder during filling and urination are measured. Use of contrast material (dye) allows the physician to take pictures during filling of the bladder and voiding, which may help evaluate other abnormalities. The electrode patches allow assessment of the function of the muscles that surround the urethra during bladder filling and urination.
- The urologist also may recommend cystoscopy. A cystoscope is a thin, flexible tube with a tiny camera on the end. It is inserted through the urethra to examine the bladder, urethra, and prostate for abnormalities that can cause urinary retention.
It’s such a common thing you may not think much about it. But every time you pee, your body is doing some pretty amazing things. Do you know why you pee? And do you know what your urine is made of?
Why We Pee
At the microscopic level, your body is constantly working to keep you healthy, even while you sleep. Complex chemical processes take place throughout the body, including the breakdown of proteins known as amino acids. When your body breaks down amino acids, ammonia is left over as waste. That’s not something you want in your body for long—ammonia is toxic to human cells.
Since ammonia is toxic to your body, you need a way to remove it. That happens partly in the liver, where the ammonia is broken down into the less-toxic chemical, urea. Urea then combines with water and gets flushed into your bladder through the kidneys as urine, protecting your body from its own chemical processes.
What Is Urine Made of?
In the simplest terms, urine is about 95% water and 5% urea and other solids. But urine is much more complex than this simple formula suggests. Urine contains five to 10 times the number of chemical compounds found in other common body fluids like saliva—more than 3,000 different chemical compounds in total. Your pee contains the remnants of the various foods you eat, as well as drug byproducts, bacterial waste, cosmetics, and chemicals found in your environment.
Why Study Urine?
You may be wondering why your doctor asks you to pee in a cup. This test could be ordered to look for signs of a specific disease or condition. But it can also be used to provide general information about your health.
The exact contents of your urine can tell doctors a lot about you. Medical professionals use a diagnostic tool called urinalysis to take a careful look at the chemical makeup of your urine. Urinalysis can reveal warnings signs for various diseases and conditions, such as hyperglycemia (high blood sugar), diabetes, kidney stones and many others. In the following slides, learn more about the clues left in your pee that can tip you off to your urinary health.
Kasper, D.L., et al., eds. Harrison's Principles of Internal Medicine, 19th Ed. United States: McGraw-Hill Education, 2015.