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Ponstel Side Effects

Generic name: mefenamic acid

Medically reviewed by Last updated on Mar 9, 2024.

Note: This document contains side effect information about mefenamic acid. Some dosage forms listed on this page may not apply to the brand name Ponstel.

Applies to mefenamic acid: oral capsule.


Oral route (Capsule)

NSAIDs cause an increased risk of serious cardiovascular thrombotic events, including myocardial infarction and stroke, which can be fatal. This risk may occur early in treatment and may increase with duration of use. Mefenamic acid is contraindicated in the setting of CABG surgery. NSAIDs can also cause an increased risk of serious gastrointestinal (GI) adverse events including bleeding, ulceration, and perforation of the stomach or intestines, which can be fatal. These events can occur at any time during use and without warning symptoms. Elderly patients and patients with a prior history of peptic ulcer disease or GI bleeding are at greater risk for serious GI events.

Serious side effects of Ponstel

Along with its needed effects, mefenamic acid (the active ingredient contained in Ponstel) may cause some unwanted effects. Although not all of these side effects may occur, if they do occur they may need medical attention.

Check with your doctor immediately if any of the following side effects occur while taking mefenamic acid:

More common

Less common


Get emergency help immediately if any of the following symptoms of overdose occur while taking mefenamic acid:

Symptoms of overdose

Other side effects of Ponstel

Some side effects of mefenamic acid may occur that usually do not need medical attention. These side effects may go away during treatment as your body adjusts to the medicine. Also, your health care professional may be able to tell you about ways to prevent or reduce some of these side effects.

Check with your health care professional if any of the following side effects continue or are bothersome or if you have any questions about them:

More common

Less common


For Healthcare Professionals

Applies to mefenamic acid: oral capsule.


Common (1% to 10%): Abdominal pain, constipation, diarrhea, dyspepsia, flatulence, gross bleeding/perforation, heartburn, nausea, gastric ulcers, duodenal ulcers, vomiting

Rare (less than 0.1%): Eructation, pancreatitis

Frequency not reported: Peptic ulcer, dry mouth, esophagitis, gastritis, GI bleeding, glossitis, hematemesis, melena, rectal bleeding, stomatitis, anorexia, colitis, enterocolitis, pyrosis, steatorrhea, GI inflammation, ulcerative stomatitis, exacerbation of Crohn's disease, gastritis[Ref]


The most frequently reported side effects were gastrointestinal (GI) in nature and included abdominal pain, constipation, diarrhea, dyspepsia, flatulence, gross bleeding/perforation, heartburn, nausea, vomiting, and gastric or duodenal ulcers.[Ref]


Rare (less than 0.1%): Hypotension, arrhythmia, myocardial infarction, palpitations, vasculitis

Frequency not reported: Congestive heart failure, tachycardia, hypertension, cardiac failure, arterial thrombotic events[Ref]


Common (1% to 10%): Anemia, bleeding time increased

Rare (less than 0.1%): Agranulocytosis, hemolytic anemia, aplastic anemia, lymphadenopathy, pancytopenia

Frequency not reported: Eosinophilia, leukopenia, thrombocytopenia, bone marrow hypoplasia, hematocrit decreased, thrombocytopenic purpura, disseminated intravascular coagulation, neutropenia, autoimmune hemolytic anemia, eosinophilia, platelet aggregation inhibition[Ref]

Cases of autoimmune hemolytic anemia have been reported with continuous use of this drug for 12 months or longer. In such cases, the Coombs tests were positive for both accelerated RBC production and destruction. The process was reversible upon discontinuation of therapy.[Ref]


Rare (less than 0.1%): Hyperglycemia

Frequency not reported: Hyponatremia, glucose intolerance, anorexia[Ref]

Nervous system

Common (1% to 10%): Dizziness, headache, drowsiness

Rare (less than 0.1%): Convulsions, coma

Frequency not reported: Syncope, paresthesia, somnolence, tremors, optic neuritis[Ref]


Rare (less than 0.1%): Respiratory distress, pneumonia

Frequency not reported: Asthma, dyspnea, bronchospasm, aggravated asthma, laryngeal edema[Ref]


Common (1% to 10%): Rash, pruritus

Rare (less than 0.1%): Angioedema, toxic epidermal necrolysis, Stevens-Johnson syndrome, erythema multiforme, exfoliative dermatitis, urticaria

Frequency not reported: Ecchymosis, purpura, alopecia, photosensitivity, sweating[Ref]


Common (1% to 10%): Elevated liver enzymes

Rare (less than 0.1%): Liver failure

Frequency not reported: Hepatitis, jaundice, cholestatic jaundice, hepatorenal syndrome, mild hepatic toxicity[Ref]


Rare (less than 0.1%): Conjunctivitis

Frequency not reported: Blurred vision, eye irritation, reversible loss of color vision, visual disturbances[Ref]


Frequency not reported: Cystitis, dysuria, hematuria, oliguria, polyuria, proteinuria, false positive urobilinogen urine[Ref]


Common (1% to 10%): Abnormal renal function

Frequency not reported: Interstitial nephritis, renal failure, allergic/non-allergic glomerulonephritis, nephrotic syndrome, non-oliguric renal failure, renal papillary necrosis, tubulointerstitial nephritis[Ref]


Rare (less than 0.1%): Hallucinations

Frequency not reported: Anxiety, confusion, depression, dream abnormalities, insomnia, nervousness[Ref]


Rare (less than 0.1%): Anaphylactoid/anaphylactic reaction

Frequency not reported: Hypersensitivity reaction, non-specific allergic reaction[Ref]


Common (1% to 10%): Edema, tinnitus

Rare (less than 0.1%): Death, meningitis, appetite changes, hearing impairment

Frequency not reported: Fever, infection, sepsis, weight changes, asthenia, malaise, vertigo, aseptic meningitis, ear pain, face edema, fatigue, malaise, multi-organ failure, pyrexia, fluid retention, edema of the larynx[Ref]


1. Product Information. Ponstel (mefenamic acid). Pfizer U.S. Pharmaceuticals Group. 2006.

2. Cerner Multum, Inc. UK Summary of Product Characteristics.

3. Cerner Multum, Inc. Australian Product Information.

4. MHRA. Medicines and Health Regulatory Agency. MHRA Drug Safety Update. 2013.

Further information

Always consult your healthcare provider to ensure the information displayed on this page applies to your personal circumstances.

Some side effects may not be reported. You may report them to the FDA.