A drug that has been used in various urinary syndromes and as an antispasmodic. Its therapeutic usefulness and its mechanism of action are not clear. It may have local anesthetic activity and direct relaxing effects on smooth muscle as well as some activity as a muscarinic antagonist. [PubChem]
Indication
For symptomatic relief of dysuria, urgency, nocturia, suprapubic pain, frequency and incontinence as may occur in cystitis, prostatitis, urethritis, urethrocystitis/urethrotrigonitis.
Pharmacology
Flavoxate is a spasmolytic flavone derivative that acts by relaxing the smooth muscle in the urinary tract. Flavoxate is a competitive muscarinic receptor antagonist indicated for the treatment of overactive bladder with symptoms of urge urinary incontinence, urgency, and urinary frequency. Muscarinic receptors play an important role in several major cholin-ergically mediated functions, including contractions of urinary bladder smooth muscle and stimulation of salivary secretion.
Toxicity
The oral LD50 for flavoxate HCl in rats is 4273 mg/kg. The oral LD50 for flavoxate HCl in mice is 1837 mg/kg. Symptoms of overdose include convulsions, decreased ability to sweat, (warm, red skin, dry mouth, and increased body temperature), hallucinations, increased heart rate and blood pressure, and mental confusion.
Affected Organisms
Humans and other mammals
Absorption
Well absorbed from gastrointestinal tract.
Elimination
57% of the flavoxate HCl was excreted in the urine within 24 hours.