From the Guidelines
If ondansetron (Zofran) is not effective for vomiting, the next medication to try would typically be aprepitant, which has been shown to be effective in preventing nausea and vomiting in patients receiving highly and moderately emetogenic chemotherapy 1.
Mechanism of Action
Aprepitant works by selectively blocking the binding of substance P at the NK-1 receptor in the central nervous system, providing a different and complementary mechanism of action to other antiemetics.
Efficacy
Studies have shown that aprepitant, in combination with ondansetron and dexamethasone, is more effective than the two-drug regimen alone in controlling both acute and delayed emesis in patients receiving emetogenic chemotherapy 1.
Dosage
The recommended dosage of aprepitant is 125 mg orally on day 1, followed by 80 mg orally on days 2 and 3, in combination with a 5-HT3 receptor antagonist and dexamethasone.
Considerations
It's essential to consider the underlying cause of vomiting when selecting the next agent, as certain conditions may respond better to specific medications. Also, be aware that aprepitant may interact with other medications, such as corticosteroids, and the dose of oral/i.v. corticosteroids should be reduced to 50%/75% when combined with aprepitant 1.
Alternative Options
Other options, such as palonosetron, may also be considered, especially if aprepitant is not available or not suitable for the patient 1.
Key Points
- Aprepitant is a effective option for preventing nausea and vomiting in patients receiving highly and moderately emetogenic chemotherapy.
- Aprepitant works by blocking the NK-1 receptor in the central nervous system.
- The recommended dosage of aprepitant is 125 mg orally on day 1, followed by 80 mg orally on days 2 and 3.
- Aprepitant may interact with other medications, such as corticosteroids.
From the FDA Drug Label
Δ Difference (%): Aprepitant 40 mg minus Ondansetron. * Estimated odds ratio for Aprepitant versus Ondansetron. A value of >1 favors Aprepitant over Ondansetron. Treatment n/m (%)Aprepitant vs Ondansetron ΔOdds ratio*Analysis Primary Endpoints No Vomiting 0 to 24 hours (Superiority)(no emetic episodes) Aprepitant 40 mg246/293 (84.0)12.6%2.1P<0.001† Ondansetron200/280 (71. 4)
The next medication to try if ondansetron (Zofran) is not effective for vomiting is Aprepitant (40 mg), as it has shown to be effective in preventing vomiting in patients who have not responded to ondansetron, with a 12.6% improvement over ondansetron in the 0 to 24 hours following the end of surgery 2.
From the Research
Next Line of Treatment for Vomiting
If ondansetron (Zofran) is not effective for vomiting, the next medication to consider is:
- Aprepitant (Emend), a neurokinin-1 (NK(1)) receptor antagonist, which has been shown to alleviate the emetic effects of substance P 3, 4, 5, 6
Dosage and Administration
The recommended dosage of aprepitant is:
- 125 mg on day 1, followed by 80 mg once daily on days 2 and 3, when combined with a standard regimen of a corticosteroid (dexamethasone) and a serotonin 5-HT(3) receptor antagonist (ondansetron) 3, 4
Efficacy and Safety
Aprepitant has been shown to be effective in preventing acute and delayed chemotherapy-induced nausea and vomiting (CINV) associated with highly emetogenic chemotherapy (HEC) and moderately emetogenic chemotherapy (MEC) 3, 4, 5 The addition of aprepitant to a standard regimen of intravenous ondansetron and oral dexamethasone has been shown to reduce chemotherapy-induced nausea and vomiting and is generally well tolerated 4, 6