|This article needs additional citations for verification. (February 2011)|
|Systematic (IUPAC) name|
|Licence data||US FDA:|
|Pregnancy cat.||B3 (AU) C (US)|
|Legal status||POM (UK) ℞-only (US)|
|Half-life||45 to 68 hours|
|Excretion||Renal (69.2%) and fecal (22.5%)|
|Mol. mass||362.465 g/mol|
| (what is this?)
Solifenacin (INN, trade name Vesicare) is a urinary antispasmodic of the antimuscarinic class. It is used in the treatment of overactive bladder with or without urge incontinence. It is manufactured and marketed by Astellas.
Mechanism of action
Solifenacin is a competitive cholinergic receptor antagonist. The binding of acetylcholine to these receptors, particularly the M3 receptor subtype, plays a critical role in the contraction of smooth muscle. By preventing the binding of acetylcholine to these receptors, solifenacin reduces smooth muscle tone in the bladder, allowing the bladder to retain larger volumes of urine and reducing the number of micturition, urgency and incontinence episodes. Because of a long elimination half life, a once-a-day dose can offer 24 hour control of the urinary bladder smooth muscle tone.
Solifenacin should not be taken by people with a history of previous hypersensitivity to it, urinary retention, gastric retention, uncontrolled or poorly controlled closed-angle glaucoma, or severe liver disease (Child-Pugh class C). It is also contraindicated in long QT syndrome, as solifenacin, like tolterodine and darifenacin, binds to HERG channels and may prolong the QT interval.
Solifenacin is metabolized in the liver by the cytochrome P450 enzyme CYP3A4. When administered concomitantly with drugs that inhibit CYP3A4, such as ketoconazole, the metabolism of solifenacin is impaired, leading to an increase in its concentration in the body and a reduction in its excretion. The manufacturer recommends that the dosage of solifenacin not exceed 5 mg a day if it is taken with a potent CYP3A4 inhibitor.
A 2006 cost-effectiveness study found that 5 mg solifenacin had the lowest cost and highest effectiveness among anticholinergic drugs used to treat overactive bladder in the United States, with an average medical cost per successfully treated patient of $6863 per year.
- Goldman, Lee (2011). Goldman's Cecil Medicine (24th ed.). Philadelphia: Elsevier Saunders. p. 343. ISBN 1437727883.
- Lexi-Comp (December 2009). "Solifenacin". The Merck Manual Professional. Retrieved on June 10, 2011.
- Ko Y, Malone DC, Armstrong EP (Dec 2006). "Pharmacoeconomic evaluation of antimuscarinic agents for the treatment of overactive bladder". Pharmacotherapy 26 (12): 1694–702. doi:10.1592/phco.26.12.1694. PMID 17125433.