Trospium chloride, a quaternary ammonium antimuscarinic, is a genitourinary antispasmodic.1, 3
Trospium chloride is used in the management of overactive bladder for the relief of symptoms associated with voiding such as urge urinary incontinence, urgency, and frequency.1, 3, 5 In two 12-week randomized, placebo-controlled clinical studies in adults 19-94 years of age with overactive bladder, trospium chloride 20 mg twice daily was more effective than placebo in reducing the number of micturitions per 24 hours1, 2, 3 and the number of urge incontinence episodes per week1, 3 and increased the volume of urine voided per micturition.1, 2 In the first clinical study of 523 adults 21-90 years of age with overactive bladder receiving trospium chloride 20 mg twice daily or placebo, urinary frequency decreased from baseline by a mean of 2.4 or 1.3 micturitions per 24 hours, urge incontinence episodes decreased from baseline by a mean of 15.4 or 13.9 occurrences per week, and urine volume voided per micturition was increased by a mean of 32.1 or 7.7 mL per micturition, respectively.1, 2, 3 In the second nearly identical study of 658 adults 19-94 years of age receiving trospium or placebo, urinary frequency decreased from baseline by a mean of 2.7 or 1.8 micturitions per 24 hours, urge incontinence episodes decreased from baseline by a mean of 16.1 or 12.1 occurrences per week, and urine volume voided per micturition was increased by a mean of 35.6 or 9.4 mL per micturition, respectively.1 The differences in outcomes (number of micturitions per 24 hours, number of urge incontinence episodes per week, urine volume voided per micturition) between trospium and placebo cohorts were statistically significant for both studies.1, 2, 3
Trospium appears to be as effective as immediate-release preparations of oxybutynin or tolterodine in decreasing urinary frequency,2, 4, 5, 6 and limited information indicates the drug may be more effective than immediate-release preparations of tolterodine in decreasing urgency incontinence compared with placebo.5, 6 However, some clinicians state that trospium appears to offer no advantage over extended-release anticholinergic preparations for the treatment of overactive bladder.3
Trospium chloride is administered orally at least 1 hour before meals or on an empty stomach.1 For the management of overactive bladder, the usual dosage of trospium chloride in adults is 20 mg twice daily.1
For patients with severe renal impairment (creatinine clearance less than 30 mL/minute), the recommended dosage is 20 mg once daily at bedtime.1
In geriatric patients 75 years of age or older, dosage may be reduced to 20 mg once daily based on patient tolerance.1
Urinary retention, gastric retention, or uncontrolled angle-closure glaucoma or risk of these conditions.1
Known hypersensitivity to trospium chloride or any ingredient in the formulation.1
Because of the risk of urinary retention, use with caution in patients with clinically important bladder outflow obstruction.1
May decrease GI motility; use with caution in patients with ulcerative colitis, intestinal atony, and myasthenia gravis.1 Because of the risk of gastric retention, trospium should be used with caution in patients with obstructive GI disorders.1
Controlled Narrow-angle Glaucoma
In patients being treated for angle-closure glaucoma, trospium should be used only if the potential benefits outweigh the risks and then only with careful monitoring.1
Category C. (See Users Guide.)
Distributed into milk in small amounts in rats; not known whether trospium is distributed into human milk.1 Use with caution in nursing women and only if potential benefit justifies the risk to the infant.1
Safety and efficacy not established in pediatric patients.
In patients 75 years of age and older, an increased incidence of adverse anticholinergic effects unrelated to drug exposure was observed; therefore, dosage may be reduced in such patients depending on patient tolerance.1 (See Dosage and Administration: Special Populations.)
Use with caution in patients with moderate or severe hepatic impairment.1
Pharmacokinetics were substantially altered in patients with severe renal impairment (creatinine clearance less than 30 mL/per minute).1 Dosage reduction is recommended in such patients.1 (See Dosage and Administration: Special Populations.) Pharmacokinetics not studied in patients with mild or moderate renal impairment.1
Adverse effects occurring in 5% or more of patients receiving trospium include dry mouth1, 2, 3 and constipation.1, 2
Drugs Affecting Hepatic Microsomal Enzymes
Inhibitors of cytochrome P-450 (CYP) isoenzymes: pharmacokinetic interactions unlikely.1, 2, 7
Drugs Metabolized by Hepatic Microsomal Enzymes
Substrates of CYP isoenzymes 1A2, 3A4, 2A6, 2C9, 2C19, 2D6, or 2E1: pharmacokinetic interactions unlikely at clinically relevant concentrations.1, 2, 7
Potential pharmacokinetic interaction (altered absorption because of decreased GI motility).1
Potential pharmacologic interaction (additive sedative effects).1
Potential pharmacologic interaction (additive anticholinergic effects).1
Potential pharmacokinetic interaction (decreased renal elimination and increased serum concentrations of trospium and/or digoxin).1, 3
Potential pharmacokinetic interaction (decreased renal elimination and increased serum concentrations of trospium and/or metformin).1, 3
Potential pharmacokinetic interaction (decreased renal elimination and increased serum concentrations of trospium and/or morphine).1, 3
Potential pharmacokinetic interaction (decreased renal elimination and increased serum concentrations of trospium and/or pancuronium).1
Potential pharmacokinetic interaction (decreased renal elimination and increased serum concentrations of trospium and/or procainamide).1, 3
Potential pharmacokinetic interaction (decreased renal elimination and increased serum concentrations of trospium and/or tenofovir).1
Potential pharmacokinetic interaction (decreased renal elimination and increased serum concentrations of trospium and/or vancomycin).1
Trospium chloride, a quaternary ammonium antimuscarinic, antagonizes acetylcholine at muscarinic receptors in cholinergically innervated organs.1, 3, 5 Its parasympatholytic action reduces the tonus of smooth muscle in the urinary bladder.1, 3 In urodynamic studies in patients with conditions characterized by involuntary detrusor contractions, trospium increased maximum cystometric capacity and volume at first detrusor contraction.1, 5 At concentrations achieved following usual therapeutic doses of the drug, trospium has little or no affinity for nicotinic receptors compared with muscarinic receptors.1, 7
Trospium chloride is incompletely absorbed from the GI tract following oral administration.1, 3, 5, 7 The mean absolute oral bioavailability is about 9.6%.1 Administration of trospium chloride with a high-fat meal reduces systemic exposure to and peak plasma concentrations of the drug by about 70-80%.1, 3 The drug is hydrophilic and theoretically should not cross the blood-brain barrier like lipophilic anticholinergic drugs (e.g., oxybutynin, tolterodine); therefore, adverse CNS effects (e.g., dizziness) should be minimal.5, 7 Following oral administration of radiolabeled trospium chloride, approximately 85% of the dose was excreted in feces and about 5.8% was eliminated in urine; unchanged drug accounted for about 60% of the recovered radioactivity in urine.1, 2, 3, 5 Active tubular secretion is a major route of elimination of trospium, implying possible competition for renal secretion with other drugs that are eliminated by the same route.1 (See Drug Interactions.) Metabolic pathways of trospium have not been fully elucidated to date; however, the cytochrome P-450 (CYP) enzyme system is not expected to contribute substantially to elimination of the drug.1, 2, 7 Based on in vitro studies, trospium does not appear likely to inhibit CYP isoenzymes 1A2, 3A4, 2A6, 2C9, 2C19, 2D6, or 2E1 at clinically relevant concentrations.1
Importance of informing patients of potential adverse anticholinergic effects (e.g., dizziness, blurred vision, heat prostration when used in a hot environment).1
Importance of using alcohol with caution, since it may enhance drowsiness caused by trospium.1
Importance of taking trospium chloride on an empty stomach or at least 1 hour before meals, and if a dose is skipped, taking the next scheduled dose at least 1 hour before the next meal.1
Importance of women informing clinicians if they are or plan to become pregnant or plan to breast-feed.1
Importance of informing clinicians of existing or contemplated concomitant therapy, including prescription and OTC drugs and dietary or herbal supplements as well as any concomitant illnesses.1
Importance of advising patients of other important precautionary information.1 (See Cautions.)
Additional Information
Overview® (see Users Guide). For additional information on this drug until a more detailed monograph is developed and published, the manufacturer's labeling should be consulted. It is essential that the manufacturer's labeling be consulted for more detailed information on usual cautions, precautions, contraindications, potential drug interactions, laboratory test interferences, and acute toxicity.
Excipients in commercially available drug preparations may have clinically important effects in some individuals; consult specific product labeling for details.
Please refer to the ASHP Drug Shortages Resource Center for information on shortages of one or more of these preparations.
AHFS® Drug Information. © Copyright, 1959-2025, Selected Revisions January 1, 2006. American Society of Health-System Pharmacists, Inc., 4500 East-West Highway, Suite 900, Bethesda, MD 20814.
1. Odyssey Pharmaceuticals. Sanctura™ (trospium chloride) tablets prescribing information. East Hanover, NJ; 2004. From Sanctura website ([Web]/Sanctura_Prescribing_Information.pdf).
2. Zinner N, Gittelman M, Harris R et al. Trospium chloride improves overactive bladder symptoms: a multicenter phase II trial. J Urol . 2004; 171:2311-5. [PubMed 15126811]
3. Anon. Trospium Chloride (Sanctura): Another anticholinergic for overactive bladder. Med Lett Drugs Ther . 2004; 46:63-4. [PubMed 15289745]
4. Halaska M, Ralph G, Wiedemann A et al. Controlled, double-blind, multicentre clinical trial to investigate long-term tolerability and efficacy of trospium chloride in patients with detrusor instability. World J Urol . 2003; 20:392-9. [PubMed 12811500]
5. Hashim H, Abrams P. Drug treatment of overactive bladder. Efficacy, cost and quality-of-life considerations. Drugs . 2004; 64:1643-56. [PubMed 15257626]
6. UK Medicines Information Pharmacists Group. Trospium. New Medicines on the market. Evaluated Information for the NHS . 2002 Feb. From UKMi website ([Web])
7. Rovner ES. Trospium chloride in the management of overactive bladder. Drugs . 2004; 64:2433-2446. [PubMed 15482001]