aprepitant vs dexamethasone

PlainMeds reviewed this comparison against our methodology in August 2026. It places FDA and CMS record fields side by side, without recommending either medication.

Side-by-side comparison of aprepitant and dexamethasone. Data from FDA drug databases (Orange Book, NDC Directory, recalls, shortages) covering 20,000+ approved drugs, plus CMS pricing; see our methodology.

minor Known Drug Interaction

Depending on the clinical situation (e.g., elderly patients) and degree of monitoring available, reduce the dose of intravenous midazolam Single 40 mg dose of aprepitant No dosage adjustment of the benzodiazepine needed Dexamethasone Clinical Impact Increased dexamethasone exposure [see Clinical Pharmacology ( 12.3 )]. Intervention 3-day aprepitant regimen Reduce the dose of oral dexamethasone by approximately 50% [see Dosage and Administration ( 2.1 )]. Single 40 mg dose of aprepitant No dosage adjustment of oral dexamethasone needed Methylprednisolone Clinical Impact Increased...

Drug Class
aprepitant NK1 Receptor Antagonist (Antiemetic)
dexamethasone Corticosteroid
Type
aprepitant Prescription
dexamethasone Prescription
Summary
aprepitant

Aprepitant (Emend) is a medicine that helps prevent nausea and vomiting. It belongs to a class of drugs called NK1 receptor antagonists.

dexamethasone

Dexamethasone (Decadron) is a corticosteroid medicine. It helps reduce inflammation and suppress the immune system.

What It Treats
aprepitant

Aprepitant is used to prevent nausea and vomiting caused by chemotherapy. It can be used for both strong and moderate chemotherapy treatments. It is also used to prevent nausea and vomiting after surgery in adults.

dexamethasone

This medicine treats many conditions, including allergies, skin problems, and breathing issues. It can also help with certain cancers, hormone problems, and nervous system disorders. Dexamethasone can also be used for short-term relief of arthritis and other joint problems.

How It Works
aprepitant

Aprepitant blocks a substance in your body called substance P. Substance P can trigger nausea and vomiting. By blocking it, aprepitant helps reduce these side effects.

dexamethasone

Dexamethasone works by decreasing inflammation in the body. It also changes how your immune system works. This can help reduce symptoms of various conditions.

Common Side Effects
aprepitant
  • Tiredness
  • Diarrhea
  • Weakness
  • Upset stomach
  • Stomach pain
dexamethasone
  • Increased appetite
  • Weight gain
  • Fluid retention
  • Mood swings
  • Insomnia
FAERS Reports
aprepitant
  • Nausea 2,145
  • Fatigue 1,769
  • Pyrexia 1,589
  • Diarrhoea 1,542
  • Dyspnoea 1,508
dexamethasone
  • Fatigue 16,525
  • Diarrhoea 16,515
  • Plasma Cell Myeloma 13,768
  • Nausea 13,495
  • Pneumonia 13,291
Serious Warnings
aprepitant

Aprepitant can interact with other medicines. It can affect how well warfarin (a blood thinner) and hormonal birth control work. If you take warfarin, your doctor will check your blood. If you use hormonal birth control, use a backup method while taking aprepitant and for 28 days after your last dose.

dexamethasone

If you have a systemic fungal infection, you should not take this medicine. Long-term use can also make it harder for your body to respond to stress.

Pregnancy
aprepitant

There is not enough information about the safety of aprepitant during pregnancy. Talk to your doctor if you are pregnant or plan to become pregnant. It is not known if aprepitant passes into breast milk, so discuss breastfeeding with your doctor.

dexamethasone

Talk to your doctor if you are pregnant or breastfeeding before taking this medicine. Dexamethasone may harm an unborn baby. It can also pass into breast milk.

Also Compare, Nearby Drugs

How to Read This aprepitant vs dexamethasone Comparison

aprepitant is classified in the NK1 Receptor Antagonist (Antiemetic) drug class, while dexamethasone sits within the Corticosteroid class. Drugs from different classes work through distinct mechanisms, so a head-to-head comparison illustrates trade-offs rather than equivalence. Both drugs are prescription-only, so a licensed provider must authorize use.

Adverse event totals above are pulled from the FDA's Adverse Event Reporting System (FAERS). For these top-ranked reactions alone, aprepitant has 8,553 submissions while dexamethasone has 73,594. Those figures reflect cumulative reporting volume, not per-patient risk, so older, widely dispensed drugs typically look worse on count alone. These two drugs have a known minor interaction flagged in FDA labeling, attributed to aprepitant slows down how your body breaks down dexamethasone, which causes the steroid levels to stay in your system longer.. Serious warnings, pregnancy guidance, and contraindications can differ even when indications overlap.

A table cannot represent individual circumstances. Data here is sourced from FDA Structured Product Labels (SPL) and FAERS, both of which update as manufacturers and clinicians submit new information. This registry does not provide medical, treatment, substitution, or medication-change directions for aprepitant or dexamethasone.

Registry boundary: This comparison displays source-record fields and does not provide individualized medical direction.