However it doesn't cause central nervous system side effects like some other muscarinic antagonists.

[4] Chemically it is a quaternary ammonium cation which causes it to stay in periphery rather than crossing the blood–brain barrier.

Trospium chloride is used for the treatment of overactive bladder with symptoms of urge incontinence and frequent urination.

[3][4][2] It should not be used with people who retain urine, who have severe digestive conditions, myasthenia gravis, narrow-angle glaucoma, or tachyarrhythmia.

[3] It should be used with caution in people who have problems with their autonomous nervous system (dysautonomia) or who have gastroesophageal reflux disease, or in whom fast heart rates are undesirable, such as people with hyperthyroidism, coronary artery disease and congestive heart failure.

Trospium chloride blocks the effect of acetylcholine on muscarinic receptors organs that are responsive to the compounds, including the bladder.

[12] Administration with a high fat meal resulted in reduced absorption, with AUC and Cmax values 70 to 80% lower than those obtained when trospium chloride was administered while fasting.

[12] Protein binding ranged from 50 to 85% when concentration levels of trospium chloride (0.5 to 50 ng/mL) were incubated with human serum in vitro.

Data taken from in vitro human liver microsomes investigating the inhibitory effect of trospium on seven cytochrome P450 isoenzyme substrates (CYP1A2, 2A6, 2C9, 2C19, 2D6, 2E1, and 3A4) suggest a lack of inhibition at clinically relevant concentrations.

[13][14] The first regulatory approval was granted in Germany in August 1999 to Madaus AG for Regurin 20 mg Tablets.

[25] A month before, Indevus had received FDA approval for an extended release formulation that allowed once a day dosing, Sanctura XR.

[26] Indevus had developed intellectual property around the extended release formulation which it licensed to Madaus for most of the world.

[29] As of 2016, the drug is available worldwide under many brand names and formulations, including oral, extended release, suppositories, and injections.

[29][30] In 2007 Indevus partnered with Alkermes to develop and test an inhaled form of trospium chloride as a treatment for COPD; it was in Phase II trials at that time.