Generic Name: Diflunisal

  • What is this medication and its most common uses?

    Diflunisal is a nonsteroidal anti-inflammatory drug (NSAID) used to treat pain, rheumatoid arthritis, and osteoarthritis.

  • What should I know when beginning and continuing on this medication?

    How does this medication work?

    Diflunisal blocks a substance in your body that is involved in causing inflammation and pain in parts of the body where there is pain and arthritis.

    What are the beneficial effects of this medication and when should I begin to have results?

    What: Diflunisal has been shown to relieve pain and arthritis symptoms, such as swelling and stiffness.

    When: Diflunisal may reduce your pain within 1 hour of taking a dose.

    How do I know it is working?

    You may feel a relief in your pain and arthritis symptoms after you start taking diflunisal. This is a good indicator that the medicine is working. Your healthcare provider may ask you questions to assess how well your symptoms are controlled.

  • What are the possible side effects of this medication?

    The following is not a full list of side effects. Side effects cannot be anticipated. If any develop or change in intensity, tell your healthcare provider as soon as possible. Only your healthcare provider can determine if it is safe for you to continue taking this medication.

    Diflunisal may increase the chance of a life-threatening heart attack or stroke. The risk of heart attack or stroke may be increased with longer use and in people who have heart disease. Call your healthcare provider right away if you develop chest pain, shortness of breath, weakness, or slurring of your speech while taking diflunisal.

    Diflunisal should never be used right before or after a heart surgery called a coronary artery bypass graft (CABG).

    Diflunisal can cause ulcers and bleeding in the stomach and intestines at any time during treatment. Ulcers and bleeding can be life-threatening and may happen without warning symptoms. The chance of a person getting an ulcer or bleeding increases with longer use, smoking, drinking alcohol, older age, having poor health, and if you are taking medicines called corticosteroids (such as prednisone) or blood thinners (such as warfarin). Call your healthcare provider right away if you develop stomach pain, indigestion, bloody or tarry stools, or you vomit blood while taking diflunisal.

    More common side effects may include: nausea, upset stomach, stomach pain, diarrhea.

    Less common side effects may include:

    Liver problems with symptoms such as nausea, tiredness, weakness, itching, yellowing of your skin or the whites of your eyes, right upper stomach pain, and flu-like symptoms.

    Serious allergic reactions with symptoms such as skin rash, blisters, fever, itching, trouble breathing, or swelling of your face or throat.

    Reye's syndrome, a potentially life-threatening disease of the brain and liver that most commonly occurs in children after a viral infection, such as chickenpox.

    Diflunisal may cause high blood pressure, kidney or eye problems, anemia (low red blood cell counts), or unexplained weight gain or swelling.

  • Who should not take this medication?

    Do not take diflunisal if you are allergic to it or any of its ingredients.

    Do not take diflunisal if you have had an asthma attack, hives, or other allergic reaction with aspirin or any other NSAID (such as ibuprofen or naproxen).

    Do not take diflunisal for pain right before or after a heart bypass surgery.

    Do not take diflunisal during the late stages of your pregnancy.

  • What should I tell my healthcare provider before I take the first dose of this medication?

    Tell your healthcare provider about all prescription, over-the-counter, and herbal medications you are taking before beginning treatment with diflunisal. Also, talk to your healthcare provider about your complete medical history, especially if you have asthma; high blood pressure; heart failure; kidney or liver problems; a history of ulcers or bleeding in your stomach or intestines; or if you are pregnant, plan to become pregnant, or are breastfeeding.

  • What is the usual dosage?

    The information below is based on the dosage guidelines your healthcare provider uses. Depending on your condition and medical history, your healthcare provider may prescribe a different regimen. Do not change the dosage or stop taking your medication without your healthcare provider's approval.


    Adults and adolescents ≥12 years: The recommended starting dose is 1000 milligrams (mg) once, followed by 500 mg every 12 hours.

    Osteoarthritis and Rheumatoid Arthritis

    Adults and adolescents ≥12 years: The recommended dose is 500 to 1000 mg a day in two divided doses.

    Your healthcare provider may adjust your or your child's dose appropriately.

  • How should I take this medication?

    Take diflunisal exactly as prescribed by your healthcare provider. Do not change your dose without first talking to your healthcare provider.

    Swallow diflunisal tablets whole. Do not crush or chew the tablets.

  • What should I avoid while taking this medication?

    Do not take other NSAIDs in combination with diflunisal without first talking to your healthcare provider.

  • What are the possible food and drug interactions associated with this medication?

    If diflunisal is taken with certain other drugs, the effects of either could be increased, decreased, or altered. It is especially important to check with your healthcare provider before combining diflunisal with the following: acetaminophen, antacids, aspirin, blood thinners (such as warfarin), certain blood pressure/heart medications (such as lisinopril or valsartan), cyclosporine, lithium, methotrexate, other NSAIDs (such as indomethacin, sulindac, or naproxen), or water pills (such as furosemide or hydrochlorothiazide).

  • May I receive this medication if I am pregnant or breastfeeding?

    Do not take diflunisal if you are in the late stage of your pregnancy. The effects of diflunisal during early pregnancy are unknown. Diflunisal can be found in your breast milk if you take it while breastfeeding. Do not breastfeed while you are taking diflunisal. Tell your healthcare provider immediately if you are pregnant, plan to become pregnant, or are breastfeeding.

  • What should I do if I miss a dose of this medication?

    If you miss a dose of diflunisal, take it as soon as you remember. However, if it is almost time for your next dose, skip the one you missed and return to your regular dosing schedule. Do not take two doses at once.

  • How should I store this medication?

    Store at room temperature.

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I'm Kristen Dore, PharmD. Welcome to PDR Health!

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