Palonosetron N-oxide is a metabolite of the serotonin (5-HT) receptor subtype 5-HT3 antagonist palonosetron .1 It is also a potential impurity in palonosetron preparations.2 Palonosetron N-oxide is a degradation product formed by exposure to oxidative stress.
1.Stoltz, R.A., Cyong, J.-C., Shah, A., et al.Pharmacokinetic and safety evaluation of palonosetron, a 5-hydroxytryptamine-3 receptor antagonist, in U.S. and Japanese healthy subjectsJ. Clin. Pharmacol.44(5)520-531(2004) 2.Vishnu Murthy, M., Srinivas, K., Kumar, R., et al.Development and validation of a stability-indicating LC method for determining palonosetron hydrochloride, its related compounds and degradation products using naphthalethyl stationary phaseJ. Pharm. Biomed. Anal.56(2)429-435(2011)