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Millions of people suffer from frustrating and embarrassing bladder control problems. These conditions, which interfere with the ability to control when and how much urination occurs, can make simple, everyday activities a challenge and social lives very difficult. Sufferers may have to cut back on hobbies or stop working. They may feel trapped by a fear of leaking accidents, the need to be close to a bathroom at all times, and an overall preoccupation with their bladders.

The three main types of over active bladders are:

• Urge Incontinence -Urge incontinence is generally considered one of the most disturbing symptoms. It is characterized by a strong desire to void that is associated with an involuntary loss of urine.

• Urgency- Urinary urgency is defined as the sensation of impending urination.

• Frequency- Frequency is typified by bladder emptying before the bladder is full.

  Over 13 million American men and women of all ages suffer from incontinence, which causes them to leak urine. Bladder control problems or overactive bladder is a common cause of urinary incontinence. Urinary incontinence is not a disease, but instead a sign that a problem exists in the urinary tract. It is considered an important condition to treat, because it can lead to social isolation, low self-esteem, depression and dependence. There are six major types of incontinence: stress, urge, mixed, overflow, neurogenic and post-prostatectomy.

  Urinary incontinence is a widespread problem known to affect the physical and emotional well-being of millions of American men and women. The disorder increases the risk of hospitalization and admission to long-term care facilities and has been associated with the loss of independence and other deleterious effects on quality of life. Indeed, many patients attempt to manage the problem by using bulky incontinence pads, restricting fluid intake, and limiting their daily activities and lifestyles. Those suffering with urinary incontinence frequently hesitate to seek medical attention because of embarrassment or lack of awareness of successful treatments. Nevertheless, international research indicates many patients are willing to bear the cost of treatments that reduce symptoms. In 1995, the estimated cost of urinary incontinence in the United States was more than $26 billion; 96% of that cost was for treatment (Figure 1 and Figure 2).

  About Overactive Bladdders
  The term "overactive bladder" describes a constellation of symptoms that includes urge urinary incontinence, urgency, and frequency. Urinary urgency is defined as the sensation of impending urination; frequency is typified by the bladder emptying before the bladder is full. Urge incontinence is generally considered one of the most disturbing of these symptoms and is characterized by a strong desire to urinate that is associated with an involuntary loss of urine. Two primary bladder abnormalities can cause urge urinary incontinence. The more common abnormality is detrusor muscle instability, in which patients have involuntary detrusor contractions due to non-neuropathic or unknown reasons.

  The other common abnormality, detrusor hyperreflexia, is characterized by involuntary detrusor contractions caused by known neurologic conditions, such as stroke, spinal cord lesions, or multiple sclerosis. In addition to urge urinary incontinence, other urinary incontinence subtypes are stress, mixed (urge and stress), overflow, functional, and reflex incontinence (Table 1). Conventional therapy for urinary incontinence may include behavioral, pharmacologic, and, in some cases, surgical treatment.

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  Prevalence
  The symptoms of overactive bladder include urge urinary incontinence, urgency, and frequency. Detrusor instability, a frequent cause of overactive bladder, is most common among the elderly and affects more women than men. The prevalence of urinary incontinence ranges from 15% to 35% in the elderly population living at home. The condition is present in more than one half of the 1.5 million nursing home residents in the United States. A review of the published literature indicates the mean prevalence of incontinence is approximately 25% in women and 6% in men aged 30 to 60 years. The same review notes that approximately 16% of women and 8% of men younger than 30 years of age report regular urine loss or incontinence.

  Anatomy of the Urinary Tract
  The bladder and urethra comprise the lower portion of the female and male urinary tracts (Figures 4 and 5), which are supported by muscles and ligaments and innervated by the brain cortex, brain stem, and thoracolumbar and sacral S2 to S4 segments of the spinal cord.

  The bladder is a hollow sac composed of four layers of muscle and connective tissue that facilitate its contractility and allow storage of urine at low pressure (Figure 6). These four layers include the serosa, the detrusor muscle, a submucosal coat of connective tissue, and the mucosa, which contains a layer of epithelial cells. The detrusor is composed of smooth muscle, and it is responsible for contracting to expel urine into the urethra during urination.

  The bladder outlet incorporates the smooth muscle (involuntary) of the proximal urethra and the striated muscles of the external urethral sphincter (Figure 6). The smooth muscle keeps the urethra closed as the bladder fills. The striated sphincter muscle contracts and complements the action of the internal sphincter when the bladder is full and pressure inside it is high.

  The autonomic nervous system regulates smooth muscle and glands and is comprised of two visceral efferent components, the sympathetic and parasympathetic nervous systems. The somatic nervous system governs transmission of impulses in the nonvisceral components of the body. The lower urinary tract is controlled by three sets of nerves: the sacral parasympathetic (pelvic nerves), the thoracolumbar sympathetic (hypogastric nerves and sympathetic chain), and the sacral somatic (pudendal nerves) (Figure 7). Urination is mediated by inhibition of somatic/sympathetic nerves and followed by activation of the parasympathetic reflex pathway. The postganglionic neurotransmitter in the parasympathetic neurons is acetylcholine. At the molecular level, activation of the uscarinic receptors is stimulated by binding of acetylcholine to the receptor. Transmission of acetylcholine in the parasympathetic nervous system causes the detrusor to contract during urination. Anticholinergic agents inhibit the binding of acetylcholine to the cholinergic receptor and suppress involuntary bladder contractions. The neurotransmitter of the sympathetic nervous system is noradrenaline (norepinephrine), and its release facilitates urine storage by signaling the detrusor to relax and the urethra to contract.