Desfesoterodine is an active metabolite of antimuscarinic drugs for the treatment of overactive bladder fesoterodine and tolterodine. In contrast to the cytochrome P450 (CYP) 2D6-mediated metabolism of tolterodine, desfesoterodine formation from fesoterodine occurs via ubiquitous nonspecific esterases. Serum levels of the desfesoterodine in humans are generally comparable to those of tolterodine following oral administration of the parent compound. The pharmacological in vitro and in vivo profiles of desfesoterodine are almost identical to those of tolterodin. The potent antimuscarinic action of desfesoterodine on the urinary bladder was confirmed in the in vivo studies and, like tolterodine, desfesoterodine was significantly more potent in inhibiting bladder contractions than salivation in the anaesthetised cat. Desfesoterodine is more potent than tolterodine in vivo. The apparent difference in potency in vivo might be explained by the degree of serum protein binding of the two compounds. The fraction of unbound drug in serum is larger for desfesoterodine than for tolterodine. Desfesoterodine may contribute to the therapeutical action of tolterodine.

Desfesoterodine is an active metabolite of antimuscarinic drugs for the treatment of overactive bladder fesoterodine and tolterodine. In contrast to the cytochrome P450 (CYP) 2D6-mediated metabolism of tolterodine, desfesoterodine formation from fesoterodine occurs via ubiquitous nonspecific esterases. Serum levels of the desfesoterodine in humans are generally comparable to those of tolterodine following oral administration of the parent compound. The pharmacological in vitro and in vivo profiles of desfesoterodine are almost identical to those of tolterodin. The potent antimuscarinic action of desfesoterodine on the urinary bladder was confirmed in the in vivo studies and, like tolterodine, desfesoterodine was significantly more potent in inhibiting bladder contractions than salivation in the anaesthetised cat. Desfesoterodine is more potent than tolterodine in vivo. The apparent difference in potency in vivo might be explained by the degree of serum protein binding of the two compounds. The fraction of unbound drug in serum is larger for desfesoterodine than for tolterodine. Desfesoterodine may contribute to the therapeutical action of tolterodine.

Alosetron, marketed under the brand name Lotronex, is a 5-HT3 antagonist used for the management of severe diarrhea-predominant irritable bowel syndrome (IBS) in women only. Alosetron is a potent and selective 5-HT3 receptor antagonist. 5-HT3 receptors are nonselective cation channels that are extensively distributed on enteric neurons in the human gastrointestinal tract, as well as other peripheral and central locations. Activation of these channels and the resulting neuronal depolarization affect the regulation of visceral pain, colonic transit and gastrointestinal secretions, processes that relate to the pathophysiology of irritable bowel syndrome (IBS). 5-HT3 receptor antagonists such as alosetron inhibit activation of non-selective cation channels which results in the modulation of the enteric nervous system. Alosetron is used for the treating women with severe irritable bowel syndrome (IBS) accompanied by severe diarrhea (usually lasting for 6 months or more). It is only prescribed to women who do not respond to other medicines and is not to be used by women whose main IBS problem is constipation.

Oseltamivir phosphate is an ethyl ester prodrug requiring ester hydrolysis for conversion to the active form, oseltamivir carboxylate. Oseltamivir carboxylate is an inhibitor of influenza virus neuraminidase affecting release of viral particles. Oseltamivir is a well tolerated orally active neuraminidase inhibitor which significantly reduces the duration of symptomatic illness and hastens the return to normal levels of activity when initiated promptly in patients with naturally acquired influenza.