Generic Name: mefenamic acid (me-fe-NAM-ik)
Brand Name: Ponstel
Mefenamic acid is a nonsteroidal anti-inflammatory drug (NSAID). It may cause an increased risk of serious and sometimes fatal heart and blood vessel problems (eg, heart attack, stroke). The risk may be greater if you already have heart problems or if you take mefenamic acid for a long time. Do not use mefenamic acid right before or after bypass heart surgery.
Mefenamic acid may cause an increased risk of serious and sometimes fatal stomach ulcers and bleeding. Elderly patients may be at greater risk. This may occur without warning signs.
Mefenamic acid is used for:
Treating menstrual pain. It may be used for short term (not more than 7 days) treatment of mild to moderate pain. It may also be used for other conditions as determined by your doctor.
Mefenamic acid is an NSAID. Exactly how it works is not known. It may block certain substances in the body that are linked to inflammation. NSAIDs treat the symptoms of pain and inflammation. They do not treat the disease that causes those symptoms.
Do NOT use mefenamic acid if:
- you are allergic to any ingredient in mefenamic acid
- you have had a severe allergic reaction (eg, severe rash, hives, trouble breathing, growths in the nose, dizziness) to aspirin or a nonsteroidal anti-inflammatory drug (NSAID) (eg, ibuprofen, celecoxib)
- you have recently had or will be having bypass heart surgery
- you have kidney problems, ulcers, or inflammation of the stomach or bowel
- you are in the last 3 months of pregnancy
Contact your doctor or health care provider right away if any of these apply to you.
Before using mefenamic acid:
Some medical conditions may interact with mefenamic acid. Tell your doctor or pharmacist if you have any medical conditions, especially if any of the following apply to you:
- if you are pregnant, planning to become pregnant, or are breast-feeding
- if you are taking any prescription or nonprescription medicine, herbal preparation, or dietary supplement
- if you have allergies to medicines, foods, or other substances
- if you have a history of liver disease, diabetes, or stomach or bowel problems (eg, bleeding, perforation, ulcers)
- if you have a history of swelling or fluid buildup, asthma, growths in the nose (nasal polyps), or mouth inflammation
- if you have high blood pressure, blood disorders (eg, porphyria), bleeding or clotting problems, heart problems (eg, heart failure), or blood vessel disease, or if you are at risk for any of these diseases
- if you have poor health, dehydration or low fluid volume, or low blood sodium levels, you drink alcohol, or you have a history of alcohol abuse
Some MEDICINES MAY INTERACT with mefenamic acid. Tell your health care provider if you are taking any other medicines, especially any of the following:
- Anticoagulants (eg, warfarin), aspirin, corticosteroids (eg, prednisone), heparin, or selective serotonin reuptake inhibitors (SSRIs) (eg, fluoxetine) because the risk of stomach bleeding may be increased
- Magnesium hydroxide (eg, antacids) or probenecid because they may increase the risk of mefenamic acid's side effects
- Cyclosporine, lithium, methotrexate, quinolones (eg, ciprofloxacin), or sulfonylureas (eg, glipizide) because the risk of their side effects may be increased by mefenamic acid
- Angiotensin-converting enzyme (ACE) inhibitors (eg, enalapril) or diuretics (eg, furosemide, hydrochlorothiazide) because their effectiveness may be decreased by mefenamic acid
This may not be a complete list of all interactions that may occur. Ask your health care provider if mefenamic acid may interact with other medicines that you take. Check with your health care provider before you start, stop, or change the dose of any medicine.
How to use mefenamic acid:
Use mefenamic acid as directed by your doctor. Check the label on the medicine for exact dosing instructions.
- Mefenamic acid comes with an extra patient information sheet called a Medication Guide. Read it carefully. Read it again each time you get mefenamic acid refilled.
- Take mefenamic acid by mouth. It may be taken with food if it upsets your stomach. Taking it with food may not lower the risk of stomach or bowel problems (eg, bleeding, ulcers). Talk with your doctor or pharmacist if you have persistent stomach upset.
- Take mefenamic acid with a full glass of water (8 oz/240 mL) as directed by your doctor.
- If you miss a dose of mefenamic acid and you are taking it regularly, take it as soon as possible. If it is almost time for your next dose, skip the missed dose. Go back to your regular dosing schedule. Do not take 2 doses at once.
Ask your health care provider any questions you may have about how to use mefenamic acid.
Important safety information:
- Mefenamic acid may cause dizziness or drowsiness. These effects may be worse if you take it with alcohol or certain medicines. Use mefenamic acid with caution. Do not drive or perform other possibly unsafe tasks until you know how you react to it.
- Serious stomach ulcers or bleeding can occur with the use of mefenamic acid. Taking it in high doses or for a long time, smoking, or drinking alcohol increases the risk of these side effects. Taking mefenamic acid with food will NOT reduce the risk of these effects. Contact your doctor or emergency room at once if you develop severe stomach or back pain; black, tarry stools; vomit that looks like blood or coffee grounds; or unusual weight gain or swelling.
- Do NOT take more than the recommended dose or use for longer than prescribed without checking with your doctor.
- Mefenamic acid is an NSAID. Before you start any new medicine, check the label to see if it has an NSAID (eg, ibuprofen) in it too. If it does or if you are not sure, check with your doctor or pharmacist.
- Do not take aspirin while you are using mefenamic acid unless your doctor tells you to.
- Mefenamic acid may interfere with certain lab tests. Be sure your doctor and lab personnel know that you take mefenamic acid.
- Lab tests, including kidney function, complete blood cell counts, and blood pressure, may be performed while you use mefenamic acid. These tests may be used to monitor your condition or check for side effects. Be sure to keep all doctor and lab appointments.
- Use mefenamic acid with caution in the ELDERLY; they may be more sensitive to its effects, especially stomach bleeding and kidney problems.
- Mefenamic acid should be used with extreme caution in CHILDREN younger than 14 years old; safety and effectiveness in these children have not been confirmed.
- PREGNANCY and BREAST-FEEDING: Mefenamic acid may cause harm to the fetus. Do not use it during the last 3 months of pregnancy. If you think you may be pregnant, contact your doctor. You will need to discuss the benefits and risks of using mefenamic acid while you are pregnant. Mefenamic acid is found in breast milk. Do not breast-feed while taking mefenamic acid.
Possible side effects of mefenamic acid:
All medicines may cause side effects, but many people have no, or minor, side effects. Check with your doctor if any of these most COMMON side effects persist or become bothersome:
Seek medical attention right away if any of these SEVERE side effects occur:
Constipation; diarrhea; dizziness; gas; headache; heartburn; nausea; stomach upset.
Severe allergic reactions (rash; hives; itching; trouble breathing; tightness in the chest; swelling of the mouth, face, lips, or tongue); bloody or black, tarry stools; change in the amount of urine produced; chest pain; confusion; dark urine; depression; fainting; fast or irregular heartbeat; fever, chills, or persistent sore throat; mental or mood changes; numbness of an arm or leg; one-sided weakness; red, swollen, blistered, or peeling skin; ringing in the ears; seizures; severe headache or dizziness; severe or persistent stomach pain or nausea; severe vomiting; shortness of breath; sudden or unexplained weight gain; swelling of hands, legs, or feet; unusual bruising or bleeding; unusual joint or muscle pain; unusual tiredness or weakness; vision or speech changes; vomit that looks like coffee grounds; yellowing of the skin or eyes.
This is not a complete list of all side effects that may occur. If you have questions about side effects, contact your health care provider. Call your doctor for medical advice about side effects. To report side effects to the appropriate agency, please read the Guide to Reporting Problems to FDA.
If OVERDOSE is suspected:
Contact 1-800-222-1222 (the American Association of Poison Control Centers), your local poison control center, or emergency room immediately. Symptoms may include decreased urination; loss of consciousness; seizures; severe dizziness or drowsiness; severe nausea or stomach pain; slow or troubled breathing; unusual bleeding or bruising; vomit that looks like coffee grounds.Proper storage of mefenamic acid:
Store mefenamic acid at 68 to 77 degrees F (20 to 25 degrees C). Brief storage at temperatures between 59 and 86 degrees F (15 and 30 degrees C) is permitted. Store away from heat, moisture, and light. Do not store in the bathroom. Keep mefenamic acid out of the reach of children and away from pets.
- If you have any questions about mefenamic acid, please talk with your doctor, pharmacist, or other health care provider.
- Mefenamic acid is to be used only by the patient for whom it is prescribed. Do not share it with other people.
- If your symptoms do not improve or if they become worse, check with your doctor.
- Check with your pharmacist about how to dispose of unused medicine.
This information should not be used to decide whether or not to take mefenamic acid or any other medicine. Only your health care provider has the knowledge and training to decide which medicines are right for you. This information does not endorse any medicine as safe, effective, or approved for treating any patient or health condition. This is only a brief summary of general information about mefenamic acid. It does NOT include all information about the possible uses, directions, warnings, precautions, interactions, adverse effects, or risks that may apply to mefenamic acid. This information is not specific medical advice and does not replace information you receive from your health care provider. You must talk with your healthcare provider for complete information about the risks and benefits of using mefenamic acid.
Disclaimer: This information should not be used to decide whether or not to take this medicine or any other medicine. Only your health care provider has the knowledge and training to decide which medicines are right for you. This information does not endorse any medicine as safe, effective, or approved for treating any patient or health condition. This is only a brief summary of general information about this medicine. It does NOT include all information about the possible uses, directions, warnings, precautions, interactions, adverse effects, or risks that may apply to this medicine. This information is not specific medical advice and does not replace information you receive from your health care provider. You must talk with your healthcare provider for complete information about the risks and benefits of using this medicine.
More mefenamic acid resources
- mefenamic acid Advanced Consumer (Micromedex) - Includes Dosage Information
- mefenamic acid Concise Consumer Information (Cerner Multum)
- Mefenamic Acid Prescribing Information (FDA)
- Mefenamic Acid Professional Patient Advice (Wolters Kluwer)
- Mefenamic Acid Monograph (AHFS DI)
- Ponstel Prescribing Information (FDA)