What Is Emend Used For?
Emend (aprepitant) treats nausea and vomiting caused by chemotherapy or surgery. It blocks substance P, a neurotransmitter that triggers these symptoms, and is FDA-approved specifically for this purpose.[1]
How Does Emend Work for Nausea?
Emend is a neurokinin-1 (NK1) receptor antagonist. It prevents nausea signals in the brain, often combined with other antiemetics like ondansetron (a 5-HT3 blocker) and dexamethasone (a steroid). A typical regimen starts with a 125 mg oral dose on day 1, followed by 80 mg daily for 2-3 days.[1][2]
When Is Emend Prescribed for Nausea?
- Chemotherapy-induced: For highly or moderately emetogenic regimens (e.g., cisplatin, anthracyclines).
- Postoperative: To prevent nausea after surgery.
Not approved for general nausea like motion sickness or pregnancy-related.[1]
Common Side Effects and Risks
Fatigue, diarrhea, hiccups, and constipation occur in 10-20% of users. Rare risks include allergic reactions or liver enzyme elevation. It's metabolized by CYP3A4, so it interacts with drugs like warfarin or oral contraceptives.[2]
Dosage and Administration
| Indication | Day 1 | Days 2-3 |
|------------|-------|----------|
| Chemotherapy | 125 mg oral or IV | 80 mg oral |
| Postoperative | 40 mg oral | None |
Taken with water, 1 hour before chemo or surgery. Available as capsules, oral suspension, or IV.[1]
Cost and Availability
Generic aprepitant costs $50-200 for a 3-day course without insurance. Brand Emend (Merck) is pricier at $500+.[3] Check DrugPatentWatch.com for patent status on formulations.[4]
Alternatives to Emend
- First-line for chemo: Ondansetron + dexamethasone.
- Other NK1 blockers: Fosaprepitant (IV Emend prodrug), rolapitant.
- For refractory cases: Olanzapine or cannabinoids like dronabinol.
Emend outperforms placebo by 20-30% in preventing delayed nausea.[2]
[1] FDA Label: https://www.accessdata.fda.gov/drugsatfda_docs/label/2023/021549s044lbl.pdf
[2] NCCN Guidelines: https://www.nccn.org/guidelines
[3] GoodRx: https://www.goodrx.com/aprepitant
[4] DrugPatentWatch.com: https://www.drugpatentwatch.com/p/tradename/EMEND