From the Guidelines
For patients with cyclical vomiting syndrome who do not respond to ondansetron, the next step typically involves trying a combination of sumatriptan and another antiemetic agent, such as promethazine, or inducing sedation with agents like diphenhydramine or benzodiazepines, as evidenced by the most recent guidelines 1. When considering the management of cyclical vomiting syndrome (CVS), it's crucial to prioritize abortive therapy to prevent the emetic phase or reduce its severity. The goal is to administer medications as early as possible in the prodromal phase. However, for patients who transition quickly to the emetic phase without a prodrome, using abortive therapy can be challenging.
Key Considerations
- The use of sumatriptan, either via nasal spray or subcutaneous injection, in combination with an antiemetic like ondansetron, is a common approach for aborting CVS attacks 1.
- For patients who do not respond to ondansetron, alternative antiemetics such as promethazine, available in rectal suppository form, or prochlorperazine may be considered.
- Inducing sedation is often an effective strategy, with promethazine being useful in this regard, or other sedating agents like diphenhydramine or benzodiazepines may be needed in an "abortive cocktail" of medications.
- Alprazolam, available in sublingual tablet or rectal form, is another option for sedation.
Management Approach
Given the complexity of CVS and the variability in patient responses to different medications, a tailored approach is necessary. This may involve trying different combinations of medications and identifying personal triggers to avoid. During acute episodes, intravenous hydration and sedating antiemetics may be beneficial in an emergency setting, as noted in recent clinical practice updates 1.
Adjunctive Therapy
While the primary focus is on abortive therapy and managing acute episodes, some patients may also benefit from adjunctive therapies aimed at preventing episodes or addressing potential underlying mitochondrial dysfunction, such as coenzyme Q10 and L-carnitine, although these should be considered based on individual patient needs and responses to primary treatments.
From the Research
Next Steps for Patients with Cyclical Vomiting Syndrome
For patients with cyclical vomiting syndrome who do not respond to ondansetron (Zofran), the following options can be considered:
- Prophylactic therapy with tricyclic antidepressants (amitriptyline) or antiepileptics (topiramate) may be effective in reducing the frequency and severity of episodes 2
- Aprepitant, a neurokinin-1 receptor antagonist, has been shown to be effective in adults with refractory cyclical vomiting syndrome, with a significant reduction in the number of episodes, emergency department visits, and hospital admissions 3
- Co-enzyme Q10 (Co-Q) is a nutritional supplement that has demonstrated efficacy in pediatric and adult migraine, and may be considered as an option in cyclical vomiting syndrome prophylaxis, with similar levels of efficacy to amitriptyline and fewer side effects 4
- Abortive therapy with triptans or sedation may be used to manage acute episodes 2
- Treatment of comorbid conditions, such as anxiety and depression, is extremely important to improve overall patient outcomes 2, 5, 6
Key Considerations
- A biopsychosocial approach to management is recommended, taking into account the complex interplay of genetic, environmental, autonomic, and neurohormonal factors that contribute to the development of cyclical vomiting syndrome 2
- A standardized treatment regimen for cyclical vomiting syndrome should be implemented, with a focus on preventing episodes and managing symptoms 5
- Further research is needed to understand the pathophysiology of cyclical vomiting syndrome and develop targeted therapies 2, 5