Ondansetron antiemetic properties

B. Two medicines, ipecac and apomorphine, induce vomiting. Metoclopramide is a prokinetic with antiemetic properties and therefore would have the opposite of the desired effect. Morphine is an opioid with analgesic and sedating properties. Promethazine and ondansetron are also antiemetics, not emetics. 

A. Ondansetron is most effective when given at ieast 30 minutes before its antiemetic properties are needed. 

Several S-HTs receptor antagonists are used as dmgs with antiemetic properties. Ondansetron represented the first marketed drug that is based on an imidazolyl tetra-hydrocarbazolone motif. The carbonyl function appeared... 

Even before the identification of central 5-HTg receptors, 5-HTg receptor antagonists have been suggested to possess striking properties. To date, based on animal studies, several reports have shown that these drugs display anxiolytic, antipsychotic [see 3,4, 5,166,167], promnesic [72,169,170], antidepressant [136], antinociceptive [23, 171] and antiemetic [172, 173] properties, generally at low doses and without side-effects [4]. Confirmation of these results in human are necessary before drawing any definitive conclusion since, except for the antiemetic effects, data from clinical trials are few and generally limited to ondansetron. Critical reviews on the subject have recently been published [9, 235-238]. 

Ondansetron is a chiral antiemetic drug used to prevent nausea and vomiting associated with use of antineoplastics. Although chiral assays have been developed for the drug [228,229], in our search we could not find any literature that described the pharmacokinetic properties of the enantiomers of the drug in humans. 

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