| Darifenacin Hydrobromide
Classifications: anticholinergic; muscarinic receptor antagonist; bladder antispasmodic; Therapeutic: bladder antispasmodic; muscarinic receptor antagonist
Pregnancy Category: C
7.5 mg and 15 mg extended release tablets
Darifenacin is a selective M3 muscarinic receptor antagonist. Muscarinic M3 receptors play an important role in contraction
of the urinary bladder smooth muscle and stimulation of salivary secretion.
Control of urinary incontinence due to urgency and frequency.
Treatment of overactive bladder with symptoms of urge urinary incontinence, urgency, and frequency.
Hypersensitivity to the drug; severe hepatic impairment (Child-Pugh C class); urinary retention; gastric obstruction; pyloric
stenosis, ileus; urinary retention; uncontrolled narrow-angle glaucoma; pregnancy (category C).
Risk of urinary retention, clinically significant bladder outflow obstruction, renal disease; decreased GI motility, GERD,
severe constipation, ulcerative colitis; myasthenia gravis; controlled narrow-angle glaucoma; lactation.
Route & Dosage
Adult: PO 7.515 mg qd
Moderate Hepatic Impairment (Child-Pugh B Class)
Max dose: ≤ 7.5 mg qd
- Ensure that the drug is not chewed or crushed. It must be swallowed whole.
- Note: Dosage should not exceed 7.5 mg daily with moderate hepatic impairment (i.e., Child-Pugh B class) or concurrent therapy
with potent inhibitors of CYP3A4 (e.g., itraconazole, clarithromycin, nefazodone, nelfinavir, ritonavir).
- Store 15°30° C (59°86° F). Protect from light.
Adverse Effects (≥1%)Body as a Whole:
, urinary tract infection
. CNS: Headache,
asthenia, dizziness. GI: Constipation, dry mouth, dyspepsia, nausea,
abdominal pain, diarrhea
Potent inhibitors of CYP3A4 (e.g., clarithromycin, erythromycin, itraconazole, ketoconazole, nefazodone, nelfinavir,
) increase darifenacin levels. Darifenacin will cause additive anticholinergic effects with other anticholinergic
drugs. Darifenacin can increase digoxin
concentrations. Food: Grapefruit juice
may increase darifenacin levels.
1519% bioavailability. Peak:
98% protein bound. Metabolism:
Extensive hepatic metabolism
. Elimination: Renal
and fecal. Half-Life:
Assessment & Drug Effects
- Monitor for adverse effects of concurrently used drugs that have a narrow therapeutic window and are metabolized by CYP26D
(e.g., flecainide, thioridazine, or TRICYCLIC ANTIDEPRESSANTS).
- Lab tests: Monitor blood levels of digoxin with concurrent therapy and assess for S&S of digoxin toxicity.
Patient & Family Education
- Follow directions for taking the drug (see ADMINISTRATION).
- Do not drive or engage in potentially hazardous activities until response to drug is known.
- Use caution in hot environments to minimize the risk of heat prostration.
- Report any of the following to a health care provider: difficulty passing urine, unexplained nausea, or persistent constipation.