Oxybutynin Chloride

oxybutynin chloride (ox i byoo' ti nin) Albert Oxybutynin (CAN), Apo-Oxybutynin (CAN), Ditropan, Ditropan XL, Novo-Oxybutynin (CAN), Oxytrol Pregnancy Category B Drug classes

Anticholinergic Urinary antispasmodic Therapeutic actions

Acts directly to relax smooth muscle and inhibits the effects of acetylcholine at muscarinic receptors; reported to be less potent an anticholinergic than atropine but more potent as antispasmodic and devoid of antinicotinic activity at skeletal neuromuscular junctions or autonomic ganglia. Indications

• •

Relief of symptoms of bladder instability associated with voiding in patients with uninhibited neurogenic and reflex neurogenic bladder ER tablets: Treatment of signs and symptoms of overactive bladder (incontinence, urgency, frequency)

Contraindications and cautions

•

•

Contraindicated with allergy to oxybutynin, pyloric or duodenal obstruction, obstructive intestinal lesions or ileus, intestinal atony, megacolon, colitis, obstructive uropathies, glaucoma, myasthenia gravis, CV instability in acute hemorrhage. Use cautiously with hepatic, renal impairment; pregnancy; lactation.

Available forms

Tablets—5 mg; syrup—5 mg/5 mL; ER tablets—5, 10, 15 mg; transdermal patch— 3.9 mg/day Dosages ADULTS

5 mg PO bid or tid. Maximum dose is 5 mg qid. ER tablets—5 mg PO daily, up to a maximum of 30 mg/day; transdermal patch—one patch per day applied to dry, intact skin on the abdomen, hip, or buttock every 3–4 days. PEDIATRIC PATIENTS > 5 YR

5 mg PO bid. Maximum dose is 5 mg tid. Pharmacokinetics Route Oral Transdermal

Onset 30–60 min 24–48 hr

Peak 3–6 hr Varies

Metabolism: Hepatic; T1/2: Unknown

Duration 6–10 hr 96 hr

Distribution: Crosses placenta; may enter breast milk Excretion: Urine Adverse effects

• • • • • •

CNS: Drowsiness, dizziness, blurred vision, dilatation of the pupil, cycloplegia, increased ocular tension, weakness CV: Tachycardia, palpitations GI: Dry mouth, nausea, vomiting, constipation, bloated feeling GU: Urinary hesitancy, retention, impotence Hypersensitivity: Allergic reactions including urticaria, dermal effect Other: Decreased sweating, heat prostration in high environmental temperatures secondary to loss of sweating

Interactions

Drug-drug • Decreased effectiveness of phenothiazines with oxybutynin • Decreased effectiveness of haloperidol and development of tardive dyskinesia • Increased toxicity if combined with amantadine, nitrofurantoin Nursing considerations Assessment

• •

History: Allergy to oxybutynin, intestinal obstructions or lesions, intestinal atony, obstructive uropathies, glaucoma, myasthenia gravis, CV instability in acute hemorrhage, hepatic or renal impairment, pregnancy, lactation Physical: Skin color, lesions; T; orientation, affect, reflexes; ophthalmologic exam, ocular pressure measurement; P, rhythm, BP; bowel sounds, liver evaluation; renal and liver function tests, cystometry

Interventions

• •

Arrange for cystometry and other diagnostic tests before and during treatment. Arrange for ophthalmologic exam before therapy and periodically during therapy.

Teaching points

• • • •

•

Take this drug as prescribed. If using the transdermal patch, apply to dry, intact skin on the abdomen, hip, or buttock every 3–4 days (twice weekly). Remove the old system before applying a new one. Select a new site for application of each new system. Periodic bladder exams will be needed during this treatment to evaluate therapeutic response. These side effects may occur: Dry mouth (suck sugarless lozenges and use frequent mouth care); GI upset; blurred vision; drowsiness (avoid driving or performing tasks that require alertness); decreased sweating (avoid high temperatures; serious complications can occur because you will be heat intolerant). Report blurred vision, fever, rash, nausea, vomiting.

Adverse effects in Italic are more common; those in Bold are life-threatening.