Darifenacin Dosage & Rx Info | Uses, Side Effects

Darifenacin Generic Name & Formulations

Legal Class

General Description

Darifenacin (as HBr) 7.5mg, 15mg; ext-rel tabs.

Pharmacological Class

Muscarinic antagonist.

How Supplied

Contact supplier

Manufacturer

Various generic manufacturers

Mechanism of Action

Darifenacin is a competitive muscarinic receptor antagonist. Muscarinic receptors play an important role in several major cholinergically mediated functions, including contractions of the urinary bladder smooth muscle and stimulation of salivary secretion.

Darifenacin Indications

Indications

Overactive bladder with symptoms of urge urinary incontinence, urgency and frequency.

Darifenacin Dosage and Administration

Adult

Swallow whole with liquid. Initially 7.5mg once daily; may increase to 15mg once daily after 2 weeks. Moderate hepatic impairment (Child-Pugh B), concomitant potent CYP3A4 inhibitors: max 7.5mg once daily.

Children

Not established.

Darifenacin Contraindications

Contraindications

Patients with or at risk for: urinary or gastric retention, uncontrolled narrow-angle glaucoma.

Darifenacin Boxed Warnings

Not Applicable

Darifenacin Warnings/Precautions

Warnings/Precautions

Severe hepatic impairment: not recommended. Bladder outflow obstruction. GI obstruction. Severe constipation. Ulcerative colitis. Myasthenia gravis. Controlled narrow-angle glaucoma. Monitor for CNS effects esp. after initiation or dose increases; consider reducing dose or discontinue if occurs. High environmental temperatures. Pregnancy. Nursing mothers.

Darifenacin Pharmacokinetics

Metabolism

Hepatic. ~98% serum protein bound.

Elimination

Renal (60%), fecal (40%). Half-life: 13–19 hours.

Darifenacin Interactions

Interactions

Potentiated by potent CYP3A4 inhibitors (eg, ketoconazole, itraconazole, ritonavir, nelfinavir, clarithromycin, nefazadone); see Adult. May potentiate CYP2D6 substrates with narrow therapeutic indexes (eg, flecainide, thioridazine, TCAs). Additive anticholinergic effects with other anticholinergics.

Darifenacin Adverse Reactions

Adverse Reactions

Constipation, dry mouth, headache, dyspepsia, nausea, UTI, accidental injury, flu symptoms; angioedema (discontinue if occurs), CNS effects (eg, confusion, hallucination, somnolence).

Darifenacin Clinical Trials

See Literature

Darifenacin Note

Notes

Formerly known under the brand name Enablex.

Darifenacin Patient Counseling