Urispas - Drug Monograph

Introduction

Urispas (flavoxate hydrochloride) is an antispasmodic medication primarily used for the symptomatic relief of bladder dysfunction. It belongs to the class of anticholinergic/spasmolytic agents and has been clinically used for decades to manage various urinary tract conditions characterized by smooth muscle spasm.

Mechanism of Action

Flavoxate hydrochloride exerts its therapeutic effects through direct spasmolytic action on smooth muscle. The drug possesses:

• Direct smooth muscle relaxant properties, particularly on the urinary tract
• Weak anticholinergic activity (significantly less potent than atropine)
• Local anesthetic properties that contribute to its spasmolytic effects
• Primary action on the detrusor muscle of the bladder, reducing hypermotility and increasing bladder capacity

Indications

FDA-approved indications:

• Symptomatic relief of dysuria, urgency, nocturia, suprapubic pain, frequency, and incontinence associated with various urologic conditions

Common clinical uses:

• Overactive bladder symptoms
• Bladder spasms following urologic procedures
• Interstitial cystitis symptoms
• Urinary tract infections (as adjunctive therapy for symptom relief)

Dosage and Administration

• May be administered with or without food
• Tablet should be swallowed whole with water
• Dosage may be titrated based on symptom response and tolerability

• Geriatric patients: Use with caution; consider lower initial doses
• Renal impairment: Use with caution; dosage adjustment may be necessary
• Hepatic impairment: Use with caution; limited data available
• Pediatric patients: Safety and effectiveness not established

Pharmacokinetics

Contraindications

• Hypersensitivity to flavoxate hydrochloride or any component of the formulation
• Gastrointestinal obstruction
• Ileus
• Megacolon
• Severe ulcerative colitis
• Obstructive uropathy
• Myasthenia gravis

Warnings and Precautions

• Use with caution in patients with:

- Angle-closure glaucoma (may precipitate acute attack) - Cardiovascular disease - Hepatic or renal impairment - Prostatic hyperplasia - Autonomic neuropathy - Hiatal hernia associated with reflux esophagitis

• May cause drowsiness or blurred vision; caution when operating machinery
• May decrease sweating, leading to heat prostration in hot weather
• Use in pregnancy only if clearly needed (Category B)
• Excreted in breast milk; use caution during breastfeeding

Drug Interactions

• Other anticholinergic agents: Additive effects (e.g., atropine, benztropine)
• CNS depressants: Enhanced sedative effects (alcohol, benzodiazepines, opioids)
• MAO inhibitors: May enhance anticholinergic effects
• Potassium tablets: May increase risk of GI mucosal lesions
• Digoxin: Flavoxate may affect absorption

Adverse Effects

• Dry mouth
• Blurred vision
• Drowsiness
• Nausea
• Headache
• Nervousness

• Tachycardia
• Palpitations
• Constipation
• Urinary retention
• Dizziness
• Confusion (especially in elderly)
• Skin rash

• Anaphylactic reactions
• Angle-closure glaucoma
• Severe constipation leading to bowel obstruction
• Cardiac arrhythmias

Monitoring Parameters

• Comprehensive medical history
• Visual acuity and intraocular pressure (if indicated)
• Renal and hepatic function tests
• Assessment of cognitive function in elderly patients

• Symptom improvement (voiding diary if appropriate)
• Adverse effects assessment
• Visual changes
• Cognitive function in vulnerable populations
• Bowel function

• Reduction in urinary frequency
• Decreased urgency episodes
• Improved nocturia
• Reduction in bladder pain/discomfort

Patient Education

• Take exactly as prescribed; do not exceed recommended dosage
• May cause drowsiness or blurred vision; avoid driving or operating machinery until effects are known
• Maintain adequate hydration unless otherwise directed
• Report immediately: eye pain, vision changes, difficulty urinating, severe constipation, or confusion
• Use sugar-free lozenges or gum if dry mouth occurs
• Avoid excessive heat exposure due to decreased sweating ability
• Inform all healthcare providers about Urispas use
• Do not crush or chew tablets

• Store at room temperature (15-30°C)
• Keep container tightly closed
• Protect from moisture
• Keep out of reach of children

References

1. FDA Prescribing Information: Flavoxate Hydrochloride Tablets 2. Abrams P, et al. (2003). "The standardisation of terminology in lower urinary tract function." Neurourology and Urodynamics 3. Wein AJ, et al. (2019). "Campbell-Walsh Urology." 12th Edition 4. American Urological Association Guidelines on Overactive Bladder (2019) 5. Micromedex® Healthcare Series. IBM Watson Health 6. Lexicomp Online®. Wolters Kluwer Clinical Drug Information 7. Thüroff JW, et al. (2011). "EAU Guidelines on Urinary Incontinence." European Urology 8. Clinical Pharmacology [Internet]. Tampa (FL): Elsevier. Available from: clinicalkey.com