What the label lists and what reports show
Aprepitant side effects
Aprepitant's FDA label: “Most common adverse reactions (≥3%) are ( 6.1 ): Adults: fatigue, diarrhea, asthenia, dyspepsia, abdominal pain, hiccups, white blood cell count decreased, dehydration, and alanine aminotransferase increased.” FAERS holds 18,353 reports naming it through July 30, 2026; the reaction reported most often, leaving out the conditions it is used for, product-use terms and outcomes, is fatigue (1,943 reports).
- Generic listed
- A presentation discontinued
Check it at the source: the aprepitant FDA label on DailyMed (effective July 5, 2024, Merck Sharp & Dohme LLC); the FDA FAERS public dashboard.
What does the patient leaflet say about side effects?
From the patient leaflet: What are the possible side effects of EMEND?In adults taking EMEND, the most common side effects include tiredness, diarrhea, weakness, indigestion, stomach (abdominal) pain, hiccups, decrease in white blood cell count, dehydration, and changes in liver function tests. In children 6 months to 17 years of age, the most common side effects include decrease in white blood cell count, headache, diarrhea, decreased appetite, cough, tiredness, decrease in red blood cell count, dizziness, and hiccups. Tell your healthcare provider if you have any side effect that bothers you or that does not go away. These are not all of the possible side effects of EMEND. For more information ask your healthcare provider or pharmacist. Call your healthcare provider for medical advice about side effects. You may report side effects to FDA at 1-800-FDA-1088.
Source: FDA drug label, NDA021549 (Msd), as published by Merck Sharp & Dohme LLC, effective July 5, 2024 (SPL set 696f9e80-9cae-403b-de9e-078343ce4713), via openFDA; the full label on DailyMed
What does the label list?
From the label: adverse reactionsMost common adverse reactions (≥3%) are ( 6.1 ): Adults: fatigue, diarrhea, asthenia, dyspepsia, abdominal pain, hiccups, white blood cell count decreased, dehydration, and alanine aminotransferase increased.
Table 5: Most Common Adverse Reactions in Patients Receiving HEC and MEC from a Pooled Analysis of HEC and MEC Studies Reported in ≥ 3% of patients treated with the EMEND regimen and at a greater incidence than standard…
| Reaction | EMEND, ondansetron, and dexamethasone EMEND regimen (N=1412) | Ondansetron and dexamethasone Standard therapy (N=1396) |
|---|---|---|
| fatigue | 13% | 12% |
| diarrhea | 9% | 8% |
| asthenia | 7% | 6% |
| dyspepsia | 7% | 5% |
| abdominal pain | 6% | 5% |
| hiccups | 5% | 3% |
| white blood cell count decreased | 4% | 3% |
| dehydration | 3% | 2% |
| alanine aminotransferase increased | 3% | 2% |
Rows and numbers as the label prints them, under its own column headings (the first rows of a longer table where it runs on). A reaction in a trial table is not necessarily caused by the medicine, and trials differ from everyday use.
From the label: adverse reactions, continuedMost common adverse reactions (≥3%) are ( 6.1 ): Adults: fatigue, diarrhea, asthenia, dyspepsia, abdominal pain, hiccups, white blood cell count decreased, dehydration, and alanine aminotransferase increased. Pediatrics: neutropenia, headache, diarrhea, decreased appetite, cough, fatigue, hemoglobin decreased, dizziness, and hiccups. To report SUSPECTED ADVERSE REACTIONS, contact Merck Sharp & Dohme LLC at 1-877-888-4231 or FDA at 1-800-FDA-1088 or www.fda.gov/medwatch. 6.1 Clinical Trials Experience Because clinical trials are conducted under widely varying conditions, adverse reaction rates observed in the clinical trials of a drug cannot be directly compared to rates in the clinical trials of another drug and may not reflect the rates observed in clinical practice. The overall safety of EMEND was evaluated in approximately 6800 individuals. Adults In 2 active-controlled, double-blind clinical trials in patients receiving highly emetogenic chemotherapy (HEC) (Studies 1 and 2), EMEND in combination with ondansetron and dexamethasone (EMEND regimen) was compared to ondansetron and dexamethasone alone (standard therapy) [see Clinical Studies (14.1) ]. …
Source: FDA drug label, NDA021549 (Msd), as published by Merck Sharp & Dohme LLC, effective July 5, 2024 (SPL set 696f9e80-9cae-403b-de9e-078343ce4713), via openFDA; the full label on DailyMed
What do FAERS reports show?
18,353 reports list aprepitant among the medicines taken, each a report of something that happened, not proof the medicine caused it; 3,080 are coded as a death and 10,066 as a hospital stay. Counts follow how widely a medicine is used and watched, and they are not a measure of how risky it is. Of the 22 reactions below, 13 are named by the same term (in US spelling) in the label's adverse reactions, warnings or patient leaflet; a reaction the label does not name may still be there under another word, and a report does not show that the medicine caused it.
Reports received each year
The 25 most reported reactions
Source: FDA Adverse Event Reporting System (FAERS) via openFDA, reports through July 30, 2026; reactions as MedDRA preferred terms
What next?
- Aprepitant: the full record
- label, generics, price, shortages, recalls
- Report a side effect to the FDA
- MedWatch
- Side effects hub
- the most reported medicines and reactions