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diflunisal vs oxaprozin

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

moderate Known Drug Interaction

NSAIDs and Salicylates Clinical Impact: Concomitant use of oxaprozin with other NSAIDs or salicylates (e.g., diflunisal, salsalate) increases the risk of GI toxicity, with little or no increase in efficacy [ see Warnings and Precautions (5.2) ] .

Recommendation: Avoid taking these two medications at the same time to prevent unnecessary damage to your digestive system.

Drug Class
diflunisal Nonsteroidal Anti-Inflammatory Drug (NSAID)
oxaprozin Nonsteroidal Anti-Inflammatory Drug (NSAID)
Type
diflunisal Prescription
oxaprozin Prescription
Summary
diflunisal

Diflunisal is a medicine that can help with pain and swelling. It belongs to a class of drugs called NSAIDs.

oxaprozin

Oxaprozin (Daypro) is a nonsteroidal anti-inflammatory drug (NSAID). It helps to reduce pain and swelling.

What It Treats
diflunisal

Diflunisal can help with mild to moderate pain. It can also treat the symptoms of osteoarthritis and rheumatoid arthritis. You should use the lowest dose that works for you, for the shortest time needed.

oxaprozin

This medicine can help with the symptoms of osteoarthritis, rheumatoid arthritis, and juvenile rheumatoid arthritis. These conditions can cause pain, swelling, and stiffness in your joints. Oxaprozin can help you feel better by reducing these symptoms.

How It Works
diflunisal

Diflunisal reduces pain and swelling by blocking the production of certain chemicals in your body. These chemicals cause inflammation and pain. By blocking them, diflunisal helps to relieve your symptoms.

oxaprozin

Oxaprozin works by reducing substances in the body that cause pain and swelling. It blocks the production of prostaglandins. Prostaglandins contribute to inflammation and pain.

Common Side Effects
diflunisal
  • Nausea
  • Vomiting
  • Upset stomach
  • Stomach pain
  • Diarrhea
oxaprozin
  • Constipation
  • Diarrhea
  • Upset stomach
  • Nausea
  • Rash
FAERS Reports
diflunisal
  • Feeling sick to your stomach 66
  • Feeling very tired 57
  • Discomfort or aching 50
  • Allergic reaction to the medicine 47
  • Pain in your head 45
oxaprozin
  • Allergic reaction to the drug 386
  • Drug not working 178
  • Pain 151
  • Feeling sick to your stomach 134
  • Headache 104
Serious Warnings
diflunisal

NSAIDs like diflunisal can increase your risk of heart problems like heart attack and stroke, which can be deadly. This risk is higher if you take it for a long time. You should not take diflunisal if you are having heart bypass surgery. NSAIDs also raise your risk of serious stomach problems like bleeding and ulcers, which can also be deadly. Older adults are at higher risk for these stomach problems.

oxaprozin

NSAIDs like oxaprozin can increase your risk of heart problems like heart attack and stroke. This risk can happen early in treatment and may increase with longer use. You should not take this medicine if you are having heart bypass surgery. NSAIDs also increase the risk of stomach and intestine problems like bleeding and ulcers, which can be fatal. Older adults and people with a history of stomach ulcers are at higher risk.

Pregnancy
diflunisal

Tell your doctor if you are pregnant or plan to become pregnant. Taking diflunisal late in pregnancy may harm your baby. It is not known if diflunisal passes into breast milk, so talk to your doctor before breastfeeding.

oxaprozin

Taking oxaprozin after 20 weeks of pregnancy may harm your baby. Avoid taking this medicine after 30 weeks of pregnancy. Talk to your doctor if you are pregnant or plan to become pregnant.

Also Compare — Nearby Drugs

How to Read This diflunisal vs oxaprozin Comparison

diflunisal is classified in the Nonsteroidal Anti-Inflammatory Drug (NSAID) drug class, while oxaprozin sits within the Nonsteroidal Anti-Inflammatory Drug (NSAID) class. Because both drugs share the same classification, they are often considered interchangeable in theory — but clinical outcomes rarely track that cleanly. 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, diflunisal has 265 submissions while oxaprozin has 953. 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 moderate interaction flagged in FDA labeling, attributed to taking two similar pain relievers together increases the risk of stomach damage without providing any extra pain relief. this can lead to serious issues like stomach ulcers or bleeding.. Serious warnings, pregnancy guidance, and contraindications can differ even when indications overlap.

A table cannot substitute for clinical judgment. Effectiveness, tolerability, drug-drug interactions with your other medications, kidney and liver function, pregnancy status, insurance formulary, and price all feed into a decision that only a licensed prescriber can make responsibly. Data here is sourced from FDA Structured Product Labels (SPL) and FAERS, both of which update as manufacturers and clinicians submit new information. This page is for educational purposes only, is not medical advice, and should not be used to self-switch between diflunisal and oxaprozin — always consult your physician or pharmacist first.

Important: This comparison is for informational purposes only. Drug effects vary between individuals. Always consult your doctor or pharmacist for personalized medical advice.