aspirin vs oseltamivir

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 aspirin and oseltamivir. 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

7.2 Drugs Without Clinically Significant Drug Interaction with Oseltamivir Phosphate for Oral Suspension No dose adjustments are needed for either oseltamivir or the concomitant drug when coadministering oseltamivir with amoxicillin, acetaminophen, aspirin, cimetidine, antacids (magnesium and aluminum hydroxides and calcium carbonates), rimantadine, amantadine, or warfarin [see Clinical Pharmacology (12.3) ] .

Drug Class
aspirin Antiplatelet / NSAID
oseltamivir Neuraminidase Inhibitor (Antiviral)
Type
aspirin Over-the-Counter
oseltamivir Prescription
Summary
aspirin

Aspirin is a common medicine used to relieve minor pain. It can also be prescribed by your doctor for other uses.

oseltamivir

Oseltamivir (Tamiflu) is an antiviral medicine. It helps treat and prevent the flu (influenza A and B).

What It Treats
aspirin

Aspirin is used to temporarily relieve minor aches and pains. However, it works slowly. It will not quickly relieve headaches or other symptoms that need immediate relief. Ask your doctor about other uses for this medicine.

oseltamivir

This medicine treats the flu in people 2 weeks and older who have had symptoms for no more than 48 hours. It can also prevent the flu in people 1 year and older. Remember that this medicine is not a substitute for your yearly flu shot. It's important to get vaccinated every year.

How It Works
aspirin

Aspirin belongs to a class of drugs called NSAIDs and antiplatelets. It works by reducing substances in the body that cause pain and inflammation. It also helps to prevent blood clots.

oseltamivir

Oseltamivir stops the flu virus from spreading in your body. It does this by blocking a protein on the virus called neuraminidase. This helps you get better faster or prevents you from getting sick.

Common Side Effects
aspirin
  • Upset stomach
  • Heartburn
oseltamivir
  • Nausea
  • Vomiting
  • Headache
  • Pain
FAERS Reports
aspirin
  • Fatigue 31,963
  • Dyspnoea 27,179
  • Nausea 26,579
  • Diarrhoea 26,452
  • Dizziness 22,390
oseltamivir
  • Vomiting 444
  • Nausea 443
  • Headache 381
  • Pneumonia 368
  • Condition Aggravated 332
Serious Warnings
aspirin

No specific warnings noted.

oseltamivir

Rarely, this medicine has been linked to serious skin reactions and allergic reactions. Stop taking this medicine and get medical help right away if you have signs of an allergic reaction or a severe skin rash. Some people, especially children, may experience confusion or unusual behavior while taking this medicine. Watch for any changes in behavior and tell your doctor right away.

Pregnancy
aspirin

Ask your doctor for advice if you are pregnant or breastfeeding.

oseltamivir

Tell your doctor if you are pregnant or plan to become pregnant. Studies suggest this medicine does not increase the risk of birth defects. Talk to your doctor about the risks and benefits of taking this medicine while pregnant or breastfeeding.

How to Read This aspirin vs oseltamivir Comparison

aspirin is classified in the Antiplatelet / NSAID drug class, while oseltamivir sits within the Neuraminidase Inhibitor (Antiviral) class. Drugs from different classes work through distinct mechanisms, so a head-to-head comparison illustrates trade-offs rather than equivalence. Both drugs are split between OTC and prescription status, which affects access and supervision.

Adverse event totals above are pulled from the FDA's Adverse Event Reporting System (FAERS). For these top-ranked reactions alone, aspirin has 134,563 submissions while oseltamivir has 1,968. 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 there is no significant interaction between these drugs that would change how they work in your body.. 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 aspirin or oseltamivir.

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