Tolterodini tartras

Tolterodine is a competitive muscarinic receptor antagonist. Both urinary bladder contraction and salivation are mediated through cholinergic muscarinic receptors. Following oral administration, tolterodine is metabolised in the liver, resulting in the formation of the 5-hydroxymethyl derivative, a major pharmacologically active metabolite. The 5-hydroxymethyl metabolite, which exhibits antimuscarinic activity similar to that of tolterodine, contributes significantly to the therapeutic effect. Both tolterodine and the 5-hydroxymethyl metabolite display high specificity for muscarinic receptors, as both show negligible activity or affinity for other neurotransmitter receptors and other potential cellular targets, such as calcium channels. Tolterodine has a pronounced effect on bladder function. Its principal effects are an increase in residual urine, reflecting incomplete bladder emptying, and a decrease in detrusor pressure, consistent with an antimuscarinic action on the lower urinary tract. Both tolterodine and its active metabolite, 5-hydroxymethyltolterodine, act as competitive antagonists at muscarinic receptors. This antagonism results in inhibition of bladder contraction, decreased detrusor pressure, and incomplete bladder emptying.