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Terms Of Use

MEFENAMIC ACID

Brand Name(s) : Ponstan
Warnings
Uses
Side Effects
Precautions
Interactions
Overdose

MEFENAMIC ACID WARNINGS

Mefenamic acid should be used with caution in:

It should not be used in:

  • Children aged under 12 years, patients who are allergic to mefenamic acid or to any other ingredients in the medicine or to other similar pain-killers (NSAIDs), ulcers or inflammation of the stomach or intestine including inflammatory bowel disease, history of stomach or intestinal ulcers, perforation (tear) or bleeding related to previous NSAID treatment, severe heart failure, severe liver disease, severe kidney failure, previous hypersensitivity to aspirin, ibuprofen or other NSAIDs, current treatment with other NSAIDs, galactose intolerance, Lapp lactase deficiency or glucose-galactose malabsorption.

Also see list of precautions and interactions

STORAGE

Store in a cool dry place below 25ºC.

MEFENAMIC ACID USES

Mefenamic acid is used to relieve mild to moderate pain.

It is a type of analgesic or painkiller, sometimes known as a non-steroidal anti-inflammatory drug (NSAID).

It is used to provide relief from pain by blocking the production of hormones in the body (prostaglandins) that cause pain and inflammation.

In general this drug is used to relieve mild to moderate pain including muscle pain, pain after injury, headache, toothache, period pain, pain following an operation or after childbirth, and pain caused by stiff, inflamed and swollenjoints (rheumatoid arthritis and osteoarthritis)

Benefits of being on this drug can include relief from pain, inflammation and joint swelling.

Listed below are the typical uses of mefenamic acid.

  • Rheumatoid arthritis including Still's disease
  • Osteoarthritis
  • Muscular pain
  • Pain caused by injury
  • Dental pain
  • Headache
  • Pain after surgery or childbirth
  • Painful periods
  • Heavy period

On occasion your doctor may prescribe this medicine to treat a condition not on the above list. Such conditions are listed below.

HOW TO USE/TAKE

How often do I take it?

  • Take this medication orally usually three times a day, with or just after food. Swallow the tablets or capsules whole with a little water. Do not chew or break the tablets or capsules.
  • Use this medication regularly in order to get the most benefit from it.
  • Remember to use it at the same time each day - unless specifically told otherwise by your doctor.
  • It may take some hours before the full benefit of this drug takes effect. Information on the time to maximum effect is not available.
  • Certain medical conditions may require different dosage instructions as directed by your doctor.

What dose?

  • Dosage is based on your age, gender, medical condition, response to therapy, and use of certain interacting medicines.

Do I need to avoid anything?

  • Mefenamic acid may make you feel dizzy or drowsy and may affect your eyesight. If you experience any of these symptoms then do not drive or operate machinery. Consult your doctor or pharmacist for more details.

When can I stop?

  • Always complete the full course as prescribed by your doctor.

MEFENAMIC ACID SIDE EFFECTS

  • Heartburn
  • Upset stomach
  • Headache
  • Feeling sick (nausea)
  • Being sick (vomiting)
  • Constipation
  • Indigestion (dyspepsia)
  • Stomach ulcers
  • Perforation or tear of the stomach or intestine
  • Worsening of colitis or Crohn's disease
  • Blood in the stools or when being sick
  • Ulceration and inflammation of the mouth (ulcerative stomatitis)
  • Heart failure
  • High blood pressure
  • Kidney problems
  • Anaemia
  • Palpitations
  • Liver problems
  • Eyesight problems
  • Thrombocytopenic purpura (a blood disorder)
  • Increased sensitivity to light

If any of these persist or you consider them severe then inform your doctor or pharmacist. Further information about other side effects can be found in the patient information leaflet.

Tell your doctor immediately if you develop any of the following symptoms:

  • Diarrhoea
  • Feeling sick or being sick (vomiting)
  • Pain in your abdomen
  • Vomiting blood or passing black stools when you go to the toilet
  • Inflammation of the mouth and tongue, wheezing or problems with your breathing (these could be signs of an allergic reaction)
  • Any other signs of allergy including a runny nose, skin rash or feeling faint or ill
  • Swelling of the ankles or any other parts or your body
  • Blood in your water (urine) or passing too much or too little water
  • Yellowing of the skin or whites of your eyes
  • Problems with eyesight or noises in your ears
  • Dizziness, drowsiness or feeling unusually tired
  • Tingling or other strange sensations
  • Feeling depressed or confused or imagining things that are not really there
  • Unexplained fever or persistent sore throat, bruising of the skin or signs of anaemia such as feeling faint or very tired
  • Increased sensitivity of your skin to sunlight

Remember that your doctor has prescribed this medication because he or she has judged that the benefit to you is greater than the risk of side effects. Many people using this medication do not have serious side effects.

A serious allergic reaction to this drug is unlikely, but seek immediate medical attention if it occurs. Symptoms of a serious allergic reaction include: rash, itching/swelling (especially of the face/tongue/throat), dizziness, trouble breathing.

This is not a complete list of possible side effects. If you notice other effects not listed above, contact your doctor or pharmacist.

The Yellow Card Scheme allows you to report suspected side effects from any type of medicine (which includes vaccines, herbals and over the counter medicines) that you are taking. It is run by the medicines safety watchdog called the Medicines and Healthcare products Regulatory agency (MHRA). Please report any suspected side effect on the Yellow Card Scheme website.

MEFENAMIC ACID PRECAUTIONS

Before taking mefenamic acid, tell your doctor or pharmacist if you are allergic to it; or to other NSAIDs; or if you have any other allergies.

This medication should not be used if you have certain medical conditions. Before using this medicine, consult your doctor or pharmacist if you have: an allergy to mefenamic acid or to any other ingredients in the medicine or to other NSAIDs, ulcers or inflammation of the stomach or intestine including inflammatory bowel disease, history of stomach or intestinal ulcers, perforation (tear) or bleeding related to previous NSAID treatment, severe heart failure, severe liver disease, severe kidney failure, previous hypersensitivity to aspirin, ibuprofen or other NSAIDs, current treatment with other NSAIDs, galactose intolerance, Lapp lactase deficiency or glucose-galactose malabsorption.

Before using this medication, tell your doctor or pharmacist your medical history, especially any of the following: trying to become pregnant, heart problems or previous stroke, kidney problems, liver problems, circulatory problems, clotting disorders, diabetes, high cholesterol levels, are a smoker, gastrointestinal disease such as ulcerative colitis or Crohn's disease, systemic lupus erythematosus (a rare condition also known as SLE), high blood pressure, bronchial asthma or a history of asthma, epilepsy (fitting), blood or bleeding problems, are dehydrated (have lost fluid) because of being sick, diarrhoea or passing too much water (urine) or have not been drinking enough fluid.

Before having surgery, tell your doctor or dentist that you are taking this medication.

Does alcohol intake affect this drug?

  • Excessive alcohol consumption can increase the risk of having gastrointestinal bleeding.

The elderly: mefenamic acid should be used with caution in the elderly as elderly patients may be at an increased risk of side effects, particularly if they are dehydrated or have kidney problems.

Pregnancy and breastfeeding - please ensure you read the detailed information below

PREGNANCY

Mefenamic acid is not safe to take if you are, or are planning to become, pregnant. Mefenamic acid may make it difficult to become pregnant.

It is sensible to limit use of medication during pregnancy whenever possible. However, your doctor may decide that the benefits outweigh the risks in individual circumstances and after a careful assessment of your specific health situation.

If you have any doubts or concerns you are advised to discuss the medicine with your doctor or pharmacist.

BREAST FEEDING

Mefenamic acid is not safe to take if you are breastfeeding

It is sensible to limit use of medication during breastfeeding whenever possible. However, your doctor may decide that the benefits outweigh the risks in individual circumstances and after a careful assessment of your specific health situation.

If you have any doubts or concerns you are advised to discuss the medicine with your doctor or pharmacist.

MEFENAMIC ACID INTERACTIONS

Your doctor or pharmacist may already be aware of any possible drug interactions and may be monitoring you for them. Do not start, stop, or change the dosage of any medicine before checking with them first.

This drug should not be used with the following medications because very serious, possibly fatal interactions may occur:

  • Other similar pain-killers (NSAIDs)
  • If you are currently using any of these medications, tell your doctor or pharmacist before starting mefenamic acid

Before using this medication, tell your doctor or pharmacist of all prescription and non-prescription/herbal products you may use, especially of:

  • Medicines that thin the blood such as warfarin
  • Medicines for high blood pressure (hypertension)
  • Medicines for depression such as SSRIs or venlafaxine
  • Medicines for diabetes
  • Medicines for epilepsy
  • Water tablets (diuretics)
  • Cardiac glycosides such as digoxin
  • Corticosteroids
  • Ciclosporin
  • Clopidogrel
  • Iloprost
  • Erlotinib
  • Mifepristone
  • Baclofen
  • Penicillamine
  • Pentoxifylline
  • Drospirenone
  • Tacrolimus
  • Lithium
  • Methotrexate
  • Quinolone antibiotics such as ciprofloxacin ofloxacin or nalidixic acid
  • Tacrolimus
  • Aspirin
  • Ritonavir
  • Zidovudine

This information does not contain all possible interactions. Therefore, before using mefenamic acid, tell your doctor or pharmacist of all the products you use.

MEFENAMIC ACID OVERDOSE

If you or someone else swallows too much mefenamic acid or if you think a child has swallowed mefenamic acid, contact your nearest hospital casualty department or doctor immediately.

If you think you, or someone you care for, might have accidentally taken more than the recommended dose of mefenamic acid or intentional overdose is suspected, contact your local hospital, GP or if in England call 111. In Scotland call NHS 24. In Wales, call NHS Direct Wales. In the case of medical emergencies, always dial 999.

MISSED DOSE

If you miss a dose, leave out that dose completely. Take your next dose at the normal time it is due. Do not double the dose to catch up.

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Source: Selected from data included with permission and copyrighted by Boots UK Limited or TicTac Communications Ltd. This copyrighted material is sourced from a licensed data provider and is not for distribution, except as may be authorised by the applicable terms of use.
CONDITIONS OF USE: The information in this database is intended to supplement, not substitute for, the expertise and judgement of healthcare professionals. The information is not intended to cover all possible uses, directions, precautions, drug interactions or adverse events, nor should it be construed to indicate that use of a particular medicine is safe, appropriate or effective for you or anyone else. A healthcare professional should be consulted before taking any medicine, changing any diet, or discontinuing any course of treatment.

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