Ondavell Mechanism of Action

Pharmacology: Pharmacodynamic: Ondansetron is a potent, highly selective 5HT₃ receptor antagonist. Its precise mode of action in the control of nausea and vomiting is not known.
Chemotherapeutic agents and radiotherapy may cause release of 5HT in the small intestine initiating a vomiting reflex by activating vagal afferents via 5HT₃ receptors. Ondansetron blocks the initiation of this reflex.
Activation of vagal afferents may also cause a release of 5HT in the area postrema, located on the floor of the fourth ventricle, and this may also promote emesis through a central mechanism.
Thus, the effect of ondansetron in the management of the nausea and vomiting induced by cytotoxic chemotherapy and radiotherapy is probably due to antagonism of 5HT₃ receptors on neurons located both in the peripheral and central nervous system.
The mechanisms of action in post-operative nausea and vomiting are not known but there may be common pathways with cytotoxic induced nausea and vomiting.
Ondansetron does not alter plasma prolactin concentrations.
Clinical Studies: ONDAVELL 4 mg ODF: The bioequivalence study shared that ONDAVELL 4 mg ODF is bioequivalent to comparator drugs. Pharmacokinetic parameters of ONDAVELL 4 mg ODF shown the area under the plasma concentration-time curve (AUC_0-t) is 104.65 ± 46.26 ngxh/mL, the AUC_0-∞ values is 108.91 ± 48.87 ngxh/mL, maximum concentration (C_max) is 14.82 ± 5.30 ng/mL, elimination half life (t_1/2) is 4.61 ± 0.98 h, and time to maximum concentration (t_max) is 2.06 ± 0.46 h.
ONDAVELL 8 mg ODF: The bioequivalence study shared that ONDAVELL 8 mg ODF is bioequivalent to comparator drugs. Pharmacokinetic parameters of ONDAVELL 8 mg ODF shown the area under the plasma concentration-time curve (AUC_0-t) is 272.76 ± 96.33 ngxh/mL, the AUC_0-∞ values is 281.78 ± 99.80 ngxh/mL, maximum concentration (C_max) is 41.13 ± 15.81 ng/mL, elimination half life (t_1/2) is 4.73 ± 0.81 h, and time to maximum concentration (t_max) is 1.80 ± 0.62 h.