The Primary Reason for Stemetil Discontinuation
The most prominent reason for the discontinuation of the Stemetil syrup formulation was the discovery of a chemical impurity known as N-nitrosomethylphenylamine (NMPA). In late 2022, the Medicines and Healthcare products Regulatory Agency (MHRA) in the UK issued a Class 2 Medicines Recall for all batches of Stemetil 5mg/5ml Syrup manufactured by Sanofi.
- Safety Concerns: The recall was a precautionary measure because nitrosamines like NMPA are classified as probable human carcinogens based on animal studies. While the immediate risk was considered low, long-term exposure to levels above the acceptable limit was deemed unsafe.
- Manufacturer Action: Sanofi, the marketing authorization holder, permanently ceased the supply of the syrup in response to the laboratory test results.
Broader Market Factors and Formulation Issues
Beyond the specific impurity recall for the syrup, other Stemetil and generic prochlorperazine formulations have faced discontinuation or shortages due to diverse market-based reasons in different regions over time. These include:
- Manufacturing and Supply Disruptions: In some markets, manufacturers have cited increased demand and supply chain issues as reasons for discontinuing or limiting the availability of prochlorperazine tablets. For example, the brand name Compazine (prochlorperazine) was discontinued in the U.S., though generics may still be available.
- Regional Cancellations: The Australian Therapeutic Goods Administration (TGA) has listed cancellations for various prochlorperazine products, including suppositories and tablets, citing market withdrawal by the sponsors.
- Complex Formulations: A case report highlighted significant harm caused to a child who was switched from the liquid prochlorperazine mesilate to a crushed tablet of prochlorperazine maleate. This was due to the liquid's discontinuation in the UK, and the case underscores that these different salt forms are not bioequivalent and require careful dose adjustments, illustrating the risks of off-label use.
Alternatives to Stemetil for Nausea and Vertigo
For patients affected by the discontinuation, several alternatives exist, but a healthcare professional must evaluate the best option based on the underlying condition, severity, and patient-specific factors. These alternatives include:
- Prescription Medications: Drugs such as ondansetron (Zofran), promethazine (Phenergan), and metoclopramide (Reglan) are commonly used to treat nausea and vomiting caused by various conditions, including chemotherapy, surgery, and gastroenteritis.
- Antihistamines: Medications like meclizine (Antivert, Dramamine Less Drowsy) are effective for vertigo and motion sickness by calming signals in the brain.
- Vestibular Rehabilitation: Specific head movements, like the Epley maneuver, and exercises can help reposition displaced crystals in the inner ear that cause vertigo.
- Natural Remedies: Ginger has been shown to be effective in reducing nausea and dizziness in some studies.
Comparison of Stemetil Alternatives
| Medication | Primary Use | Key Side Effects | Availability | Comments |
|---|---|---|---|---|
| Stemetil (prochlorperazine) | Nausea, vomiting, vertigo, anxiety | Drowsiness, dizziness, dry mouth, blurred vision, potential for tardive dyskinesia | Discontinued in some formulations and regions | Specific formulations (e.g., syrup) recalled due to impurity |
| Ondansetron (Zofran) | Nausea/vomiting (chemotherapy, surgery) | Headache, constipation, diarrhea, fatigue | Prescription | A serotonin antagonist, different mechanism than prochlorperazine |
| Promethazine (Phenergan) | Nausea/vomiting, motion sickness, sleep aid | Drowsiness, dizziness, blurred vision | Prescription (often) | A phenothiazine like prochlorperazine, but typically with less neuroleptic effects |
| Meclizine (Antivert) | Vertigo, motion sickness | Drowsiness, dry mouth, blurred vision | Prescription and Over-the-Counter (OTC) | Less sedating than some other options |
Important Considerations for Patients
If you were previously prescribed Stemetil, it is crucial to consult your doctor or pharmacist before making any changes to your medication. Never stop taking prochlorperazine abruptly, especially after long-term use, as this can trigger withdrawal symptoms.
Potential withdrawal symptoms can include:
- Nausea and vomiting
- Dizziness
- Tremors or shakiness
- Insomnia
- Restlessness
Your healthcare provider can guide you through a safe and gradual withdrawal process and recommend a suitable alternative treatment plan.
Conclusion
The discontinuation of Stemetil (prochlorperazine) is not a single, universal event but rather a combination of specific safety recalls and broader market trends affecting different formulations and regions. While the presence of a carcinogenic impurity drove the recall of the syrup, other forms faced discontinuation due to manufacturing or commercial decisions. For patients, this underscores the importance of staying informed about medication changes and always consulting a healthcare professional to find safe and effective alternatives, especially given the risks of withdrawal from abrupt cessation. Information regarding your medication is always changing, so relying on expert advice is paramount. For general information on prochlorperazine, a good resource is the MedlinePlus Drug Information on Prochlorperazine.
