Related Experiment Video
Updated: Jun 4, 2026
10:26
Bladder Smooth Muscle Strip Contractility as a Method to Evaluate Lower Urinary Tract Pharmacology
Published on: August 18, 2014
Effect of caffeine on bladder function in patients with overactive bladder symptoms
Supatra Lohsiriwat1, Muthita Hirunsai, Bansithi Chaiyaprasithi
1Department of Physiology, Division of Urology, Faculty of Medicine Siriraj Hospital, Mahidol University, Bangkok, Thailand.
Urology Annals
|February 25, 2011
Summary
Caffeine intake (4.5 mg/kg) increased urination frequency and urgency in adults with overactive bladder (OAB). This study found caffeine led to increased flow rate and voided volume, suggesting caution for those with lower urinary tract symptoms.
Area of Science:
- Urology
- Pharmacology
- Nephrology
Background:
- Overactive bladder (OAB) significantly impacts quality of life.
- Caffeine is a common diuretic and stimulant with potential effects on bladder function.
Purpose of the Study:
- To investigate the urodynamic effects of a 4.5 mg/kg dose of caffeine in adults diagnosed with OAB.
- To determine if caffeine consumption alters bladder sensation, capacity, and voiding parameters.
Main Methods:
- A controlled study involving 12 participants (9 women, 3 men) aged 21-40 with OAB symptoms.
- Participants consumed 8 ml/kg of water with and without caffeine in separate sessions.
- Cystometry and uroflowmetry were conducted 30 minutes post-ingestion to assess bladder function.
Main Results:
- Caffeine ingestion decreased bladder volumes at the first desire to void and normal desire to void (P<0.05).
- A trend towards decreased volumes at strong desire, urgency, and maximum cystometric capacity was observed.
- Maximal flow rate, average flow rate, and voided volume increased significantly (P<0.05) post-caffeine, with no change in detrusor pressure.
Conclusions:
- Caffeine at 4.5 mg/kg induces diuresis and lowers the sensory threshold for bladder filling in OAB patients.
- The observed increase in flow rate and voided volume, alongside earlier urgency, suggests caffeine exacerbates OAB symptoms.
- Individuals experiencing lower urinary tract symptoms should limit or avoid caffeine consumption.
Related Concept Videos
01:19Urodynamic Studies: Uroflowmetry
Uroflowmetry is a non-invasive urodynamic test designed to measure various aspects of urination, including volume, flow rate, and the time to void. This test is crucial for diagnosing and assessing conditions such as bladder outlet obstruction, bladder dysfunction, incomplete bladder emptying, incontinence, and urinary tract blockages caused by benign prostatic hyperplasia (BPH) and urethral strictures.Pre-Test Instructions:Before a uroflowmetry test, patients are typically advised to drink...
01:22Imaging Studies VI: Voiding Cystourethrography and Cystography
Voiding Cystourethrography (VCUG) and Cystography are specialized radiographic procedures used to examine the structure and function of the bladder and urethra.Voiding Cystourethrography (VCUG)A Voiding Cystourethrogram (VCUG) is a diagnostic imaging procedure that assesses the anatomy and function of the lower urinary tract. It focuses on the bladder, bladder neck, and urethra, helping detect abnormalities such as vesicoureteral reflux (VUR)—the backward or reverse flow of urine into the...
01:23Urinary Bladder
The urinary bladder is a hollow, muscular sac that temporarily stores urine before it is expelled from the body. It can hold approximately 600 mL of urine prior to micturition. The bladder is retroperitoneal and located behind the pubic symphysis in the pelvic floor.
In males, the bladder is situated in front of the rectum, while in females, it is positioned anterior to the vagina and uterus. The bladder floor contains an inverted triangular area called the trigone, defined by the two ureteric...
In males, the bladder is situated in front of the rectum, while in females, it is positioned anterior to the vagina and uterus. The bladder floor contains an inverted triangular area called the trigone, defined by the two ureteric...
01:17Urinary Tract Infection IV: Nursing Management
In managing urinary tract infections (UTIs) in nursing, a comprehensive assessment is essential. Begin by gathering subjective data, such as the patient’s complaints of dysuria (painful urination), urinary frequency, urgency, suprapubic pain, and any lower abdominal discomfort. This information can be complemented by questions regarding previous UTIs, sexual activity, and personal hygiene practices, which can provide insight into risk factors. Objective assessment should focus on signs like...
01:28Urologic Endoscopic Procedure: Cystoscopic Examination
Meaning of Cystoscopic Examination:Cystoscopy is an essential diagnostic tool in urology that is used to assess the structure and function of the genitourinary system. It provides a direct view of the urethra, bladder, and, in some cases, the ureteral openings. This procedure helps detect structural abnormalities, infections, cancers, and blockages in the urinary tract. There are two types of cystoscopy:Flexible cystoscopy is commonly performed in outpatient settings due to its less invasive...
01:26The Micturition Reflex
Urination, or micturition involves the coordination of the bladder's detrusor muscle and two sphincters to ensure controlled bladder emptying.
The process begins with bladder filling, where the bladder wall stretches as urine accumulates. This stretching activates the urine storage reflex, mediated by the sacral spinal segments and the pontine storage center. Efferent sympathetic impulses stimulate the detrusor muscle to relax and the internal urethral sphincter to contract, facilitating urine...
The process begins with bladder filling, where the bladder wall stretches as urine accumulates. This stretching activates the urine storage reflex, mediated by the sacral spinal segments and the pontine storage center. Efferent sympathetic impulses stimulate the detrusor muscle to relax and the internal urethral sphincter to contract, facilitating urine...