Mefenamic acid is non-steroidal anti-inflammatory drug (NSAID) with anti-inflammatory, analgesic and antipyretic properties. Prostaglandins are implicated in a number of disease processes including inflammation, modulation of the pain response, dysmenorrhoea, menorrhagia and pyrexia. In common with most NSAIDs mefenamic acid inhibits the action of prostaglandin synthetase (cyclooxygenase). This results in a reduction in the rate of prostaglandin synthesis and reduced prostaglandin levels.

Pack size Box of 50 tablets, 100 tablets. Bottle of 50 tablets, 100 tablets
Shelf-life 36 months
Composition Mefenamic acid
Dosage forms and strengths Film-coated tablet: 50 mg
Product code :



  • As an anti-inflammatory analgesic for the symptomatic relief of rheumatoid arthritis (including Still’s disease), osteoarthritis, and pain including muscular, traumatic and dental pain, headaches of most aetiology, post-operative and post-partum pain.
  • Primary dysmenorrhoea.
  • Menorrhagia.


  • Adults
    1 tablet (500 mg) three times daily.
  • In menorrhagia to be administered on the first day of excessive bleeding and continued according to the judgement of the physician.
  • In dysmenorrhoea to be administered at the onset of menstrual pain and continued according to the judgement of the physician.
  • Elderly (over 65 years): As for adults.
  • It is recommended that children under 12 years of age should be given mefenamic acid suspension (50 mg/5 ml).
  • Do not exceed the stated dose.


  • Administered orally, preferably with or after food.
  • Undesirable effects may be minimised by using the lowest effective dose for the shortest duration necessary to control symptoms.
  • Hypersensitivity to mefenamic acid or any of the other ingredients.
  • Inflammatory bowel disease.
  • History of gastrointestinal bleeding or perforation, related to previous NSAIDs therapy.
  • Active, or history of recurrent peptic ulcer/haemorrhage (two or more distinct episodes of proven ulceration or bleeding).
  • Severe heart failure, hepatic failure and renal failure.
  • Because the potential exists for cross-sensitivity to aspirin, ibuprofen, or other non-steroidal anti-inflammatory drugs, mefenamic acid must not be given to patients who have previously shown hypersensitivity reaction (e.g. asthma, bronchospasm, rhinitis, angioedema or urticaria) to these medicines.
  • During the last trimester of pregnancy.
  • Treatment of pain after coronary artery bypass graft (CABG) surgery.

Most frequently

  • Diarrhoea occasionally occurs following the use of mefenamic acid. Although this may occur soon after starting treatment, it may also occur after several months of continuous use. The diarrhoea has been investigated in some patients who have continued this drug in spite of its continued presence. These patients were found to have associated proctocolitis. If diarrhoea does develop the drug should be withdrawn immediately and this patient should not receive mefenamic acid again.

Frequencies are not known for the following adverse reactions

  • Haemolytic anaemia (Reversible when mefenamic acid is stopped), anaemia, hypoplasia bone marrow, haematocrit decreased, thrombocytopenic purpura, temporary lowering of the white blood cell count (leukopenia) with a risk of infection, sepsis, and disseminated intravascular coagulation. Agranulocytosis, aplastic anaemia, eosinophilia, neutropenia, pancytopenia, thrombocytopenia.
  • Hypersensitivity reactions may consist of non-specific allergic reactions and anaphylaxis respiratory tract reactivity comprising asthma, aggravated asthma, bronchospasm, or dyspnoea or assorted skin disorders including rashes of various types, pruritus, urticaria, purpura, angioedema, and more rarely exfoliative or bullous dermatoses (including epidermal necrolysis and erythema multiforme).
  • Glucose intolerance in diabetic patients, hyponatraemia.
  • Confusion, depression, hallucinations, nervousness.
  • Optic neuritis, headaches, paraesthesia, dizziness, drowsiness, reports of aseptic meningitis (especially in patients with existing auto-immune disorders, such as systemic lupus erythematosus, mixed connective tissue disease), with symptoms such as stiff neck, headache, nausea, vomiting, fever or disorientation. Blurred vision, convulsions, insomnia.
  • Eye irritation, reversible loss of color vision, visual disturbances.
  • Ear pain, tinnitus, vertigo.
  • Oedema, hypertension and cardiac failure, increased risk of arterial thrombotic events (for example myocardial infarction or stroke). Palpitations, hypotension.
  • Asthma, dyspnoea.
  • Peptic ulcers, perforation or GI bleeding, sometimes fatal, particularly in the elderly, may occur. Nausea, vomiting, diarrhoea, flatulence, constipation, dyspepsia, abdominal pain, melaena, haematemesis, ulcerative stomatitis, exacerbation of colitis and Crohn’s disease. Less frequently, gastritis has been observed.
  • Elderly or debilitated patients seem to tolerate gastrointestinal ulceration or bleeding less well than other individuals and most spontaneous reports of fatal GI events are in this population.
  • Anorexia, colitis, enterocolitis, gastric ulceration with or without haemorrhage, pancreatitis, steatorrhea.
  • Borderline elevations of one or more liver function tests, cholestatic jaundice. Mild hepatotoxicity, hepatitis, hepatorenal syndrome.
  • Angioedema, laryngeal oedema, erythema multiforme, face oedema, bullous reactions including Lyell’s syndrome (toxic epidermal necrolysis) and Stevens-Johnson syndrome, perspiration, rash, photosensitivity reaction, pruritus and urticaria.
  • Allergic glomerulonephritis, acute interstitial nephritis, dysuria, haematuria, nephrotic syndrome, non-oliguric renal failure (particularly in dehydration), proteinuria, renal failure including renal papillary necrosis.
  • Fatigue, malaise, multi-organ failure, pyrexia.
  • A positive reaction in certain tests for bile in the urine of patients receiving mefenamic acid has been demonstrated to be due to the presence of the drug and its metabolites and not to the presence of bile.
  • Undesirable effects may be minimised by using the lowest effective dose for the shortest duration necessary to control symptoms.
  • Patients on prolonged therapy should be kept under regular surveillance with particular attention to liver dysfunction, rash, blood dyscrasias or development of diarrhoea. Appearance of any of these symptoms should be regarded as an indication to stop therapy immediately.
  • Use with concomitant NSAIDs including cyclooxygenase-2 specific inhibitors.
  • Prolonged use of any type of painkiller for headaches can make them worse. If this situation is experienced or suspected, medical advice should be obtained and treatment should be discontinued.
  • The diagnosis of “Medication overuse headache” should be suspected in patients who have frequent or daily headaches despite (or because of) the regular use of headache medications.
  • Precaution should be taken in patients suffering from dehydration and renal disease, particularly the elderly.
  • The elderly have an increased frequency of adverse reactions to NSAIDs especially gastrointestinal bleeding and perforation which may be fatal.
  • Caution is required if administered to patients suffering from, or with a previous history of, bronchial asthma since NSAIDs have been reported to precipitate bronchospasm in such patients.
  • The administration of an NSAID may cause a dose dependant reduction in prostaglandin formation and precipitate renal failure. Patients at greatest risk of this reaction are those with impaired renal function, cardiac impairment, liver dysfunction, those taking diuretics and the elderly. Renal function should be monitored in these patients.
  • NSAIDs cause an increased risk of serious cardiovascular thrombotic events, including myocardial infarction and stroke, either of which can be fatal. This risk may occur as early as the first weeks of treatment and may increase with duration of use. The cardiovascular thrombotic risk has been observed most consistently at higher doses.
    Physicians should assess periodically appearance of cardiovascular adverse events, even in the absence of previous cardiovascular symptoms. Patients should be warned about the symptoms of serious cardiovascular events and seek physicians immediately if these symptoms occur.
  • To minimize the risk for an adverse cardiovascular event in patients treated with Flaminac, prescribe the lowest effective daily dose for the shortest duration possible.
  • As NSAIDs can interfere with platelet function, they should be used in caution in patients with intracranial haemorrhage and bleeding diathesis.
  • GI bleeding, ulceration or perforation, which can be fatal, has been reported with all NSAIDs at any time during treatment, with or without warning symptoms or a previous history of serious GI events. Smoking and alcohol use are added risk factors.
    The risk of GI bleeding, ulceration or perforation is higher with increasing NSAID doses, in patients with a history of ulcer, particularly if complicated with haemorrhage or perforation, and in the elderly. Combination therapy with protective agents (e.g. misoprostol or proton pump inhibitors) should be considered for patients at risk of GI bleeding such as the elderly, and also for patients requiring concomitant low dose aspirin, or other drugs likely to increase gastrointestinal risk.
    Patients with a history of GI toxicity, particularly when elderly, should report any unusual abdominal symptoms (especially GI bleeding) particularly in the initial stages of treatment.
    Caution should be advised in patients receiving concomitant medications which could increase the risk of gastrotoxicity or bleeding such as corticosteroids, anticoagulants such as warfarin, selective serotonin reuptake inhibitors or anti-platelet agents such as aspirin.
    When GI bleeding or ulceration occurs in patients receiving mefenamic acid the treatment should be withdrawn.
  • In patients with systemic lupus erythematosus (SLE) and mixed connective tissue disorders there may be an increased risk of aseptic meningitis.
  • Serious skin reactions, some of them fatal, including exfoliative dermatitis, Stevens-Johnson syndrome, and toxic epidermal necrolysis, have been reported in association with use of NSAIDs. Mefenamic acid should be stopped at the first appearance of skin rash, mucosal lesions or any other sign of hypersensitivity.
  • The use of mefenamic acid may impair female fertility and is not recommended in women attempting to conceive. In women who have difficulties conceiving or who are undergoing investigation of infertility, withdrawal of mefenamic acid should be considered.
  • In dysmenorrhoea and menorrhagia lack of response should alert the physician to investigate other causes.
  • Caution should be exercised when treating patients suffering from epilepsy.
  • Sunset yellow may cause allergic-type reactions.
  • In patients who are known or suspected to be poor CYP2C9 metabolisers based on previous history/experience with other CYP2C9 substrates, mefenamic acid should be administered with caution as they may have abnormally high plasma levels due to reduced metabolic clearance.
  • NSAIDs should not be used during the first two trimesters of pregnancy or labour unless the potential benefit to the patient outweighs the potential risk to the foetus.
  • Mefenamic acid should not be taken by nursing mothers.
  • Undesirable effects such as dizziness, drowsiness, fatigue and visual disturbances are possible after taking NSAIDs. If affected, patients should not drive or operate machinery.