Which antiemetic is effective in treating post-operative nausea and vomiting?

Ondansetron is an effective antiemetic for treating post-operative nausea and vomiting due to its mechanism of action as a selective serotonin 5-HT3 receptor antagonist. After surgery, patients often experience nausea and vomiting as a result of anesthesia or as part of the body's physiological response to surgical trauma. Ondansetron works by blocking serotonin receptors in both the central nervous system and the gastrointestinal tract, which helps to prevent the activation of the vomiting center in the brain.

This targeted action makes Ondansetron particularly beneficial in the post-operative setting, where nausea can significantly impact recovery. It is also favored for its rapid onset of action and relatively favorable side effect profile compared to some other antiemetics. Other agents like dexamethasone can also be used for nausea but are often part of a multi-modal approach. Scopolamine is primarily used for motion sickness and is not as effective in the post-operative context, while granisetron also acts similarly to Ondansetron but is typically viewed as a second-line agent.

Thus, Ondansetron is recognized for its specific effectiveness in the prevention and treatment of post-operative nausea and vomiting, solidifying its place as a first-line choice in these situations.