From the FDA Drug Label
Metoclopramide should not be used in epileptics or patients receiving other drugs which are likely to cause extrapyramidal reactions, since the frequency and severity of seizures or extrapyramidal reactions may be increased. The patient with a seizure disorder should not take Reglan (metoclopramide) because it may increase the frequency and severity of seizures 1. There is no information in the provided drug label about Zofran (ondansetron), therefore, The FDA drug label does not answer the question regarding Zofran.
From the Research
Patients with seizure disorders should generally avoid Reglan (metoclopramide) but can usually take Zofran (ondansetron) safely. Reglan is not recommended for patients with seizure disorders because it can lower the seizure threshold and potentially increase the risk of seizures, especially at higher doses or with prolonged use. This occurs because metoclopramide blocks dopamine receptors in the brain, which can affect neuronal excitability.
Key Considerations
- Zofran, on the other hand, works through a different mechanism (5-HT3 receptor antagonism) and does not significantly affect seizure threshold, making it a safer alternative for controlling nausea and vomiting in patients with epilepsy or other seizure disorders.
- Any medication decisions should be made in consultation with a healthcare provider who knows the patient's complete medical history, current medications, and seizure control status.
- The provider may need to consider potential drug interactions with anti-seizure medications and adjust dosing accordingly.
- If Zofran is prescribed, the standard dosing is typically 4-8 mg orally or intravenously every 8-12 hours as needed for nausea and vomiting.
Relevant Studies
Studies such as 2 highlight the importance of considering the potential for certain medications to lower the seizure threshold, although this study focuses on antibiotics, the principle applies broadly to medications that can affect neuronal excitability.
Clinical Decision Making
In clinical practice, the decision to use Reglan or Zofran in a patient with a seizure disorder should be based on a thorough assessment of the patient's individual risk factors and the potential benefits and risks of each medication, as informed by the most recent and highest quality evidence available, such as 2.