DESCRIPTION:
Urispas (flavoxate HCl) tablets contain flavoxate hydrochloride, a synthetic
urinary tract spasmolytic.
Chemically, flavoxate hydrochloride is 2-piperidinoethyl 3-methyl-4-oxo-2-
phenyl-4H- 1-benzopyran-8-carboxylate hydrochloride. The empirical formula of
flavoxate hydrochloride is C24H25NO4 . HCl. The molecular weight is 427.94.
URISPAS is supplied in tablets for oral administration. Each round, white, film-
coated URISPAS tablet is debossed URISPAS SKF and contains flavoxate
hydrochloride, 100 mg. Inactive ingredients consist of calcium phosphate, castor
oil, cellulose acetate phthalate, magnesium stearate, polyethylene glycol,
starch and talc.
ACTIONS/CLINICAL PHARMACOLOGY:
Flavoxate hydrochloride counteracts smooth muscle spasm of the urinary tract and
exerts its effect directly on the muscle.
In a single study of 11 normal male subjects, the time to onset of action was 55
minutes. The peak effect was observed at 112 minutes. 57% of the flavoxate HCl
was excreted in the urine within 24 hours.
INDICATIONS AND USAGE:
Urispas (flavoxate HCl) is indicated for symptomatic relief of dysuria, urgency,
nocturia, suprapubic pain, frequency and incontinence as may occur in cystitis,
prostatitis, urethritis, urethrocystitis/urethrotrigonitis. "Urispas" is not
indicated for definitive treatment, but is compatible with drugs used for the
treatment of urinary tract infections.
CONTRAINDICATIONS:
Urispas (flavoxate HCl) is contraindicated in patients who have any of the
following obstructive conditions: pyloric or duodenal obstruction, obstructive
intestinal lesions or ileus, achalasia, gastrointestinal hemorrhage and
obstructive uropathies of the lower urinary tract.
WARNINGS:
Urispas (flavoxate HCl) should be given cautiously in patients with suspected
glaucoma.
PRECAUTIONS:
INFORMATION FOR PATIENTS: Patients should be informed that if drowsiness and
blurred vision occur, they should not operate a motor vehicle or machinery or
participate in activities where alertness is required.
CARCINOGENESIS, MUTAGENESIS, IMPAIRMENT OF FERTILITY: Mutagenicity studies and
long-term studies in animals to determine the carcinogenic potential of Urispas
(flavoxate HCl) have not been performed.
PREGNANCY: Teratogenic Effects--Pregnancy Category B. Reproduction studies have
been performed in rats and rabbits at doses up to 34 times the human dose and
revealed no evidence of impaired fertility or harm to the fetus due to flavoxate
HCl. There are, however, no well- controlled studies in pregnant women. Because
animal reproduction studies are not always predictive of human response, this
drug should be used during pregnancy only if clearly needed.
NURSING MOTHERS: It is not known whether this drug is excreted in human milk.
Because many drugs are excreted in human milk, caution should be exercised when
URIPAS is administered to a nursing woman.
PEDIATRIC USE: Safety and effectiveness in children below the age of 12 years
have not been established.
ADVERSE REACTIONS:
The following adverse reactions have been observed, but there are not enough
data to support an estimate of their frequency.
GASTROINTESTINAL: Nausea, vomiting, dry mouth.
CNS: Vertigo, headache, mental confusion, especially in the elderly, drowsiness,
nervousness.
HEMATOLOGIC: Leukopenia (one case which was reversible upon discontinuation of
the drug).
CARDIOVASCULAR: Tachycardia and palpitation.
ALLERGIC: Urticaria and other dermatoses, eosinophilia and hyperpyrexia.
OPHTHALMIC: Increased ocular tension, blurred vision, disturbance in eye
accommodation.
RENAL: Dysuria.
OVERDOSAGE:
The oral LD50 for flavoxate HCl in rats is 4273 mg./kg. The oral LD50 for
flavoxate HCl in mice is 1837 mg/kg.
It is not known whether flavoxate HCl is dialyzable.
DOSAGE AND ADMINISTRATION:
ADULTS AND CHILDREN OVER 12 YEARS OF AGE: One or two 100 mg. tablets 3 or 4
times a day. With improvement of symptoms, the dose may be reduced. This drug
cannot be recommended for infants and children under 12 years of age because
safety and efficacy have not been demonstrated in this age group.