A 2025 case report describes one hospitalized patient whose severe nausea and vomiting improved after clinicians used intravenous fosaprepitant. Standard anti-nausea medicines had not provided enough relief. The report is clinically interesting, but it is not proof that fosaprepitant works for every person with cannabinoid hyperemesis syndrome (CHS).
What the case report found
- The patient had repeated vomiting and a positive THC screen.
- Several commonly used anti-nausea treatments had not worked well enough.
- The care team then used fosaprepitant, an NK-1 receptor antagonist.
- The patient’s nausea and vomiting resolved after treatment, and she was discharged.
This was a single case. It can point researchers toward a question, but it cannot establish how often the treatment works or who should receive it.
Why CHS can be difficult to treat in the hospital
CHS can cause repeated episodes of severe nausea, vomiting, and abdominal pain. Persistent vomiting can lead to dehydration, electrolyte problems, and acute kidney injury. Those complications may require urgent treatment.
Common anti-nausea medicines do not always control CHS symptoms. In the published case, paramedics first gave the patient promethazine. The response was limited. Other treatments used during the hospital stay also did not provide enough relief.
The patient’s medical history made the situation more complex. It included diabetes, gastroparesis, hypertension, a seizure disorder, and use of semaglutide. The treating team considered several possible contributors to the vomiting. This matters because clinicians must rule out other causes before attributing symptoms to CHS.
What is fosaprepitant?
Fosaprepitant blocks neurokinin-1, or NK-1, receptors. Hospitals commonly use it to help prevent nausea and vomiting related to chemotherapy. It is the intravenous form of a medicine related to oral aprepitant.
The authors also discussed an earlier case in which oral aprepitant was used after other medicines failed. Both reports describe improvement. Even so, two case reports are still very limited evidence.
Does this make fosaprepitant a standard CHS treatment?
No. Fosaprepitant is not a proven cure for CHS, and this report does not create a new standard of care. Larger studies would be needed to compare results, risks, dosing, and patient selection.
Only a qualified clinical team can decide whether a hospital medicine is appropriate. Readers should not use this report to self-treat or to delay emergency care.
What remains the most important long-term step?
Acute treatments may help control symptoms during an episode. They do not remove the trigger. Sustained cannabis cessation remains the central step associated with CHS recovery and lower risk of recurrence.
Seek urgent medical care for persistent vomiting, inability to keep fluids down, fainting, confusion, chest pain, blood in vomit, very little urine, or other signs of severe dehydration.
CHS SOS provides general education, not diagnosis or individualized medical advice.
Selected clinical references
- AGA Clinical Practice Update on CHS diagnosis and management (2024)
- NCBI Bookshelf: Cannabinoid Hyperemesis Syndrome
- Cleveland Clinic: CHS symptoms, causes, and treatment
Sources are selected for the topic of this page. CHS SOS provides general education, not diagnosis or individualized medical advice, and does not describe content as medically reviewed unless that is explicitly stated.
Questions readers often ask
What is the main takeaway from “Fosaprepitant for Refractory CHS: What One Case Report Found”?
A plain-language review of one 2025 case report on fosaprepitant after standard anti-nausea treatments failed, including the evidence limits and the role of cannabis cessation.
What pattern makes CHS different from occasional nausea?
CHS is associated with prolonged cannabis exposure and a recurring pattern that may progress through prodromal, hyperemetic, and recovery phases. Hot bathing behavior is common, but no single symptom proves CHS.
What should I do next if I am still unsure?
Use the CHS Symptom Check to organize the pattern, review the CHS Action Plan, and bring your timeline to a qualified clinician. Seek urgent care now if severe vomiting or dehydration warning signs are present.
Medical disclaimer: CHS SOS provides educational information and does not diagnose or treat medical conditions. Seek advice from a qualified healthcare professional.
