<n0:ComplexDefinition xmlns:n0="http://ncicb.nci.nih.gov/xml/owl/EVS/ComplexProperties.xsd#"><n0:def-definition>The tartrate salt form of tolterodine, a benzhydryl compound and a muscarinic receptor antagonist possessing both antimuscarinic and antispasmodic properties. Both tolterodine and its active metabolite, 5-hydroxymethyltolterodine, competitively blocks muscarinic receptors, thereby inhibiting acetylcholine receptor binding. This antagonistic action results in an increase in residual urine, reflecting an incomplete emptying of the bladder, and a decrease in detrusor pressure, indicating an antimuscarinic action on the lower urinary tract.. The 5-hydroxymethyl metabolite appears to contribute significantly to the therapeutic effects.</n0:def-definition><n0:def-source>NCI</n0:def-source></n0:ComplexDefinition>