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Related to urination: Frequent urination


the discharge of urine from the bladder; urine from the kidneys is passed in spurts every few seconds along the ureters to the bladder, where it collects and later is passed to the outside via the urethra. Called also micturition and voiding.

The Urinary Process. Urination is a complex process controlled by muscles of the bladder and sphincter mechanism and by modulatory centers in the central and peripheral nervous systems. The detrusor muscle is a complex meshwork of interlaced smooth muscle bundles that contract in a way that squeezes urine from the bladder vesicle. The sphincter mechanism consists of smooth muscle in the bladder neck and proximal urethra, a striated muscle sphincter consisting of slow twitch muscle fibers in the urethral wall, and periurethral muscles that are a component of the pelvic floor muscles. The detrusor relaxes during bladder filling to accommodate increasing volumes at a low pressure, and the sphincter remains tightly closed. During urination, the detrusor contracts and the sphincter mechanism relaxes, allowing smooth outflow of urine.

As the bladder fills, modulatory centers in the brain prevent the occurrence of contractions. Meanwhile, the sphincter mechanism remains closed under autonomic and somatic nervous system control. During urination, the inhibition of contractions is removed and a reflex originates in the pontine micturition center. That causes the detrusor muscle to contract and the sphincter mechanism to relax. The location of the final output of central nervous system impulses to and from the bladder and sphincter is the sacral micturition center, located in spinal segments 2, 3, and 4, which must be intact for contraction to occur. Injury to the pontine micturition center will compromise the smooth coordination between sphincter mechanism and detrusor muscle, and injury to the brain will affect the volitional control of urine (bladder stability). See also urinary incontinence.


The passing of urine.
Synonym(s): miction, micturition (1) , uresis


/uri·na·tion/ (u″rĭ-na´shun) the discharge of urine.


Etymology: Gk, ouron + L, atus, process
the act of passing urine. Also called micturition, voiding.


The passing of urine.
Synonym(s): miction, micturition (1) , uresis.


the discharge of urine from the bladder; called also voiding of urine and micturition. Urine from the kidneys is passed every few seconds along the ureters to the bladder, where it collects until voided. During the act of urination the urine passes from the bladder to the outside via the urethra.

difficult urination
the bladder is continually full; the animal is straining to urinate, often grunting, but producing only a thin stream, often under great pressure. Called also dysuria, strangury.
dribbling urination
a steady, intermittent passage of small volumes of urine, sometimes precipitated by a change in posture or increase in intra-abdominal pressure, reflecting inadequate or lack of sphincter control. Seen with ectopic ureters and in paralysis of bladder. See also dribblers.
inappropriate urination
see inappropriate micturition.
increased urination frequency
if output of urine per urination is reduced the increased frequency is probably related to irritation in the tract due to cystitis or urethritis.
painful urination
dysuria; frequent passage of small amounts of urine with grunting and maintaining posture for some time afterwards.
submissive urination
an expression of behavioral submission by dogs.

Patient discussion about urination

Q. protien in urine what are the causes and preventions


Q. How you stop urinating frequently? I don't have any conditions that make me urinate often. I simply drink lots of water... Is there some trick I can employ so that I can still drink lots of water but not have to go to the bathroom so frequently?

A. I only drink water and green tea, Thanks.

Q. Today doctor removed my stunt of kidney. It inflamate while urination.. till How long i will feel like this?

A. You should consult your doctor, since instruments in the kidney and urinary tracts can cause infections (even after removing them), that may cause symptoms like you describe.

More discussions about urination
References in periodicals archive ?
Women were more likely to suffer from either kind of incontinence, while men experienced more problems with slow or incomplete urination.
June Burtonshaw, Swansea Council cabinet member, said: "Public urination is a contentious issue that has been troubling authorities, organisations and businesses working together to create a cleaner, healthier and safer city centre.
Prenatal and postnatal personal history and familial history of the patients, demographic data, reason for urodynamic evaluation, urination charts (daily fluid intake, the amount of urine and urination frequency), presence of "bladder dysfunction" findings in the history, number of UTIs, physical examination findings (including detailed neurological examination: deep tendon reflexes-anal sphincter tonus and perianal examination) and imaging results of the patients were recorded.
Oxytrol works by relaxing the bladder muscle due to the main drug, oxybutynin, which reduces the squeezing and relieve the symptoms of frequent urination.
The overall prevalence of nocturia, defined as two or more episodes of urination per night, was found to be 15.
The new agent, a selective alpha-1A receptor blocker developed by Kissei Pharmaceutical, helps improve urethral resistance and alleviate urination disorder.
The increased drinking is accompanied by an increased urination, leading to a loss of water-soluble vitamins.
In spite of a picture of dancer Frederick Saquette folding his scrotum over his penis and the brochure's--text "Everything you think dance is, Jerome Bel is not"--Whitehead claimed the festival had breached their contract with him by failing to make clear that Bel's eponymous work involved urination and manipulation of body parts.
Advanced prostate cancer can slow or weaken the urinary stream or cause frequent urination.
Autonomic neuropathy most often affects the organs that control urination and sexual function.
Like other organophosphates, chlorpyrifos exhibits moderate acute toxicity, with symptoms that include diarrhea and increased urination, perspiration, tearing of the eyes, and salivation.
Urination can be accompanied by burning or pain, and bleeding can occur, especially during intercourse.