Fesoterodine Fumarate

Fesoterodine Fumarate is a competitive muscarinic receptor antagonist. After oral administration, fesoterodine is rapidly and extensively hydrolyzed by nonspecific esterases to its active metabolite, 5-hydroxymethyl tolterodine, which is responsible for the antimuscarinic activity of fesoterodine.

Muscarinic receptors play a role in contractions of urinary bladder smooth muscle. Inhibition of these receptors in the bladder is presumed to be the mechanism by which fesoterodine produces its effects.

• Adult Overactive Bladder: Used for treatment of OAB symptoms (urge urinary incontinence, urgency, and frequency) in adults.
• Pediatric Neurogenic Detrusor Overactivity: Used for treatment of NDO in pediatric patients 6 years and older with body weight greater than 25 kg.

Other genito-urinary preparations

Muscarinic Receptor Antagonist

Fesoterodine is a competitive muscarinic receptor antagonist. After oral administration, fesoterodine is rapidly and extensively hydrolyzed by nonspecific esterases to its active metabolite, 5-hydroxymethyl tolterodine, which is responsible for the antimuscarinic activity of fesoterodine.

Fesoterodine inhibits muscarinic receptors in the bladder, reducing bladder smooth muscle contractions and increasing bladder capacity.

Adult Dose (Oral):

• Overactive Bladder: Starting: 4 mg once daily; may increase to maximum 8 mg once daily based on response and tolerability.

Pediatric Dose (NDO, 6 years and older):

• 25-35 kg: 4 mg once daily; may increase to 8 mg if needed.
• >35 kg: Starting: 4 mg once daily; after 1 week, increase to 8 mg once daily.

Swallow whole with liquid; do not chew, divide, or crush. Take with or without food.

If you miss a dose, take it as soon as possible; however, if it is almost time for your next dose, skip the missed dose.

Adult Common Side Effects (>=4%):

• Dry mouth (placebo: 7%; 4 mg: 19%; 8 mg: 35%)
• Constipation (placebo: 2%; 4 mg: 4%; 8 mg: 6%)

Pediatric Common Side Effects (>=2%):

• Diarrhea
• Urinary tract infection
• Dry mouth
• Constipation
• Abdominal pain
• Nausea
• Weight increased
• Headache

Precautions:

• Angioedema: Discontinue and provide appropriate therapy if occurs.
• Urinary Retention: Not recommended in patients with clinically significant bladder outlet obstruction.
• Decreased Gastrointestinal Motility: Not recommended in patients with severe constipation.
• Narrow-Angle Glaucoma: Use with caution.
• CNS Effects: Somnolence reported; advise patients not to drive or operate heavy machinery until they know how it affects them.
• Myasthenia Gravis: Use with caution.

Contraindications:

• Hypersensitivity
• Urinary retention
• Gastric retention
• Uncontrolled narrow-angle glaucoma

Drug Interactions:

• Antimuscarinic Drugs: May increase frequency/severity of dry mouth, constipation, urinary retention.
• Strong CYP3A4 Inhibitors (ketoconazole, itraconazole, clarithromycin): Doses greater than 4 mg not recommended.
• CYP3A4 Inducers (rifampin, carbamazepine): No dosing adjustments recommended.

Food Interactions: May be taken with or without food. Caution with alcohol.

Use in Pregnancy: No data on use in pregnant women; caution required.

Use in Lactation: No information on presence in human milk; caution required.

Pediatric Use: Safety and effectiveness established for NDO in patients 6 years and older weighing greater than 25 kg.

Geriatric Use: No dose adjustment recommended; pharmacokinetics not significantly influenced by age.

Renal Impairment: Use with caution; dose adjustment may be needed in severe renal impairment.

Hepatic Impairment: Use with caution in patients with liver disease.

Overdose: In case of overdose, symptomatic treatment should be given.

Storage: Keep below 30 degree C, away from light and moisture. Keep out of reach of children.

Fesoterodine Fumarate