Solifenacin Tablets

Mechanism

Solifenacin selectively inhibits muscarinic M3 receptors in the bladder detrusor muscle. This reduces involuntary contractions, increases bladder capacity, and decreases urinary urgency and frequency.

Pharmacokinetics

• Absorption: Well absorbed orally; peak plasma concentration in 3–8 hours.
• Distribution: Highly protein bound (~98%).
• Metabolism: Extensively metabolized in liver via CYP3A4.
• Elimination: Excreted in urine and feces.
• Half-life: ~45–68 hours.

Side Effects

• Dry mouth
• Constipation
• Blurred vision
• Drowsiness
• Urinary retention (rare)

Contraindication

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

Interaction

• CYP3A4 inhibitors: Ketoconazole, ritonavir may increase plasma levels.
• Other antimuscarinics: Additive side effects.
• Drugs causing urinary retention: Increased risk when combined.

Warning and Precautions

• Monitor patients with hepatic or renal impairment.
• Use cautiously in patients with bladder outlet obstruction.
• Advise patients about risk of drowsiness and blurred vision.
• Discontinue if severe constipation or urinary retention occurs.

Dosage

As directed by the Physician.