Oxybutynin Chloride

A to Z Drug Facts

 Action Increases bladder capacity, diminishes frequency of uninhibited contractions of detrusor muscle and delays initial desire to void.

 Indications Treatment of symptoms of bladder instability associated with voiding in patients with uninhibited and reflex neurogenic bladder (eg, urinary leakage, dysuria). Treatment of overactive bladder with symptoms of urge urinary incontinence, urgency, and frequency (oxybutynin extended-release [ER] tablet).

 Contraindications Untreated angle-closure glaucoma; untreated narrow anterior chamber angles; GI obstruction; paralytic ileus; intestinal atony of elderly or debilitated patients; toxic megacolon complicating ulcerative colitis; severe colitis; obstructive uropathy; myasthenia gravis; unstable cardiovascular status in acute hemorrhage.

 Route/Dosage

ADULTS (immediate-release tablet or syrup): PO 5 mg bid to tid (max, 5 mg qid).

CHILDREN > 5 yr: PO 5 mg bid (max, 5 mg tid). Adults (ER tablet): PO 5 mg once daily adjusted in 5 mg increments at weekly intervals (max, 30 mg daily).

 Interactions

Amantadine: Increased risk of anticholinergic side effects.

Beta-Blockers (eg, atenolol): Atenolol plasma levels may be elevated, increasing the risk of side effects.

Digoxin: Increased plasma levels of slow-dissolution oral tablets may be increased.

Haloperidol: Worsening of schizophrenic symptoms; tardive dyskinesia; decreased serum haloperidol concentrations, reducing therapeutic effect.

Phenothiazines: Decreased therapeutic effects of phenothiazines; increased incidence of anticholinergic side effects.

 Lab Test Interferences None well documented.

 Adverse Reactions

CARDIOVASCULAR: Tachycardia; palpitations; vasodilatation; hypertension, palpitation, vasodilation (ER tablet). CNS: Drowsiness; dizziness; hallucinations; insomnia; restlessness; somnolence, headache, dizziness, insomnia, nervousness, confusion (ER tablet). DERMATOLOGIC: Rash; dry skin (ER tablet). EENT: Decreased lacrimation; mydriasis; amblyopia; cycloplegia; blurred vision, dry eyes, rhinitis, sinusitis, dry nasal and sinus mucous membranes, pharyngitis (ER tablet). GI: Nausea; vomiting; decreased GI motility; diarrhea, nausea, dyspepsia, flatulence, gastroesophageal reflux (ER tablet); dry mouth; constipation. GU: Impotence; urinary tract infection, increased postvoid residual volume, cystitis (ER tablet); urinary retention and hesitancy. RESPIRATORY: Upper respiratory tract infection, cough, bronchitis (ER tablet). OTHER: Decreased sweating; asthenia; suppression of lactation; asthenia, pain, abdominal pain, accidental injury, back pain, flu-like syndrome, arthritis (ER tablet).

 Precautions

Pregnancy: Category B. Lactation: Undetermined. Children: Safety and efficacy in children < 5 yr not established. Anticholinergic Effects: Use cautiously with phenothiazines or other drugs with anticholinergic properties because side effects will be additive. Diarrhea: Diarrhea may be an early symptom of intestinal obstruction in which oxybutynin is contraindicated. Heat Prostration: Heat prostration may occur when exposed to high environmental temperature.

 Administration/Storage

• If patient experiences nausea, administer with food.
• Store in tightly closed container at room temperature.
• Oxybutynin ER tablet should be taken whole with liquid and not chewed, divided, or crushed.

 Assessment/Interventions

• Obtain patient history, including drug history and any known allergies.
• Assess patient for urinary retention before administrating drug and periodically during treatment. If symptoms of urinary retention (eg, suprapubic pain in conjunction with urgency and frequency with voiding of small amounts) occur, notify health care provider.
• If signs of heat stroke develop (eg, elevation in body temperature, dehydration, mental changes), move patient to a cooler area; cover torso with wet towels; use fans or air conditioners. Give extra fluids.
• If patient has difficulty voiding, use bladder massage.
• If passing urinary catheter becomes difficult, use extra lubricant and inflexible catheter, allow time for spasms to diminish.
• If diarrhea occurs, discontinue use and notify health care provider.

 Patient/Family Education

• Instruct patient to take sips of water frequently, suck on ice chips or sugarless hard candy, or chew sugarless gum if dry mouth occurs.
• Teach patient to use bladder massage to empty bladder.
• Advise patient to use caution in hot weather to reduce risk of heat stroke.
• Advise patient that drug may cause drowsiness or dizziness, and to use caution while driving or performing other tasks requiring mental alertness.
• Advise patient to take oxybutynin ER tablet whole with liquids and not chewed, divided, or crushed.
• Inform patient not to be concerned if noticing a tablet in the stool; the tablet shell is eliminated from the body but the drug is released from the tablet at a controlled rate.

Books@Ovid
Copyright © 2003 Facts and Comparisons
David S. Tatro
A to Z Drug Facts