amoxicillin 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 amoxicillin 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) ] .
Amoxil
Tamiflu
Amoxicillin and Clavulanate Potassium is a combination medicine used to fight bacterial infections. It contains amoxicillin, an antibiotic, and clavulanate, which helps the amoxicillin work better.
Oseltamivir (Tamiflu) is an antiviral medicine. It helps treat and prevent the flu (influenza A and B).
This medicine treats infections like lower respiratory infections, ear infections (otitis media), sinus infections, skin infections, and urinary tract infections. It works against specific bacteria that cause these infections. However, it should only be used when tests show the bacteria are susceptible to it, to avoid antibiotic resistance.
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.
Amoxicillin kills bacteria by stopping them from building cell walls. Some bacteria produce a substance called beta-lactamase, which can destroy amoxicillin. Clavulanate blocks beta-lactamase, allowing amoxicillin to effectively kill the bacteria.
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.
- • Diarrhea or loose stools
- • Nausea
- • Skin rashes
- • Hives
- • Vomiting
- • Nausea
- • Vomiting
- • Headache
- • Pain
- Chronic Kidney Disease 4,661
- Acute Kidney Injury 4,200
- Diarrhoea 4,082
- Drug Hypersensitivity 3,744
- Nausea 3,700
- Vomiting 444
- Nausea 443
- Headache 381
- Pneumonia 368
- Condition Aggravated 332
This medicine can cause serious allergic reactions, including fatal ones. Stop taking it and get medical help right away if you have any signs of an allergic reaction. This medicine can also cause severe skin reactions. Tell your doctor if you develop a rash. It can also cause liver problems and severe diarrhea.
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.
Tell your doctor if you are pregnant or plan to become pregnant. It is not known if this medicine will harm your unborn baby. Amoxicillin passes into breast milk and may cause harm to a nursing infant. Talk to your doctor before breastfeeding.
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 amoxicillin vs oseltamivir Comparison
amoxicillin is classified in the Penicillin Antibiotic 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 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, amoxicillin has 20,387 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 these two drugs do not have a meaningful impact on how the body processes or uses either medication.. 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 amoxicillin or oseltamivir.
Registry boundary: This comparison displays source-record fields and does not provide individualized medical direction.