Fesoterodine (trade name Toviaz) is a prodrug of 5-hydroxymethyl tolterodine, which is also the active metabolite of tolterodine. Fesoterodine and its active metabolites are nonsubtype selective, competitive antagonists of human muscarinic receptors, but 5-hydroxymethyl tolterodine has greater potency than the parent compound. A prodrug approach was necessary for systemic bioavailability of 5-hydroxymethyl tolterodine after oral administration. Fesoterodine was originated by Schwarz Pharma (later a subsidiary of UCB) and is being developed by Pfizer for the treatment of overactive bladder and urinary urge incontinence. The agent is launched in several countries for the treatment of overactive bladder, including the US, Japan, Canada, Europe and Asia.

Tolterodine is competitive muscarinic receptors M3 and M2 antagonist. It was sold under trade names detrol for the treatment of overactive bladder with symptoms of urge urinary incontinence. Both urinary bladder contraction and salivation are mediated via cholinergic muscarinic receptors. After oral administration, tolterodine is metabolized in the liver, resulting in the formation of the 5-hydroxymethyl derivative, a major pharmacologically active metabolite. The 5-hydroxymethyl metabolite, which exhibits an antimuscarinic activity similar to that of tolterodine, contributes significantly to the therapeutic effect. Both tolterodine and the 5-hydroxymethyl metabolite exhibit a high specificity for muscarinic receptors, since both show negligible activity and affinity for other neurotransmitter receptors and other potential cellular targets, such as calcium channels. Tolterodine has a pronounced effect on bladder function. The main effects of tolterodine at 1 and 5 hours were an increase in residual urine, reflecting an incomplete emptying of the bladder, and a decrease in detrusor pressure. These findings are consistent with an antimuscarinic action on the lower urinary tract.