Mefenamic Acid 500mg Tablets


Period pain is experienced by most women at some point in their lives as a normal part of their menstrual cycle. The pain can be felt in the tummy and sometimes the back and thighs. The pain can feel like either intense spasms (cramps) or a constant dull ache. Mefenamic Acid is a non-steroidal anti-inflammatory drug that tackles period pain head-on shortly after being taken, easing your discomfort to get on with your day. It can also be used to relieve moderately severe pain, such as muscular aches and pains, headaches, and dental pain.


Period pain is common and a normal part of your menstrual cycle. Most women experience it at some point in their lives.

It’s usually felt as painful muscle cramps in the tummy, which can spread to the back and thighs.

The pain sometimes comes in intense spasms, while at other times it may be dull but more constant.

What causes period pain?

Period pain occurs when the muscular wall of the womb tightens (contracts).
During your period, the wall of the womb starts to contract more vigorously to encourage the womb lining to shed away as part of your monthly period.

When the muscular wall of the womb contracts, it compresses the blood vessels lining your womb. This temporarily cuts off the blood supply – and hence oxygen supply – to your womb. Without oxygen, the tissues in your womb release chemicals that trigger pain.

While your body is releasing these pain-triggering chemicals, it’s also producing other chemicals called prostaglandins. These encourage the womb muscles to contract more, further increasing the level of pain.

Period pain caused by a condition

Less commonly, period pain can be caused by an underlying medical condition. Doctors sometimes call this secondary dysmenorrhoea.

Period pain linked to an underlying condition tends to affect older women. Women aged 30 to 45 are most commonly affected.

Conditions that can cause period pain include:

endometriosis – where cells that normally line the womb start to grow in other places, such as in the fallopian tubes and ovaries; these cells can cause intense pain when they shed and fall away
fibroids – non-cancerous tumours that can grow in the womb and can make your periods heavy and painful
pelvic inflammatory disease – where your womb, fallopian tubes and ovaries become infected with bacteria, causing them to become severely inflamed
adenomyosis – where the tissue that normally lines the womb starts to grow within the muscular womb wall, making your periods particularly painful

Product Description

What is Mefenamic Acid

Mefenamic Acid (brand name Ponstan) is a prescription only medication available in the UK. Mefenamic acid is a nonsteroidal anti-inflammatory drug (NSAID) and can be used to treat period pain by reducing inflammation and provides an effective pain relief. These medicines reduce pain and inflammation, and bring down a high temperature and works by reducing hormones that cause inflammation and pain in the body.

Mefenamic acid is commonly used to treat menstrual pain.

Mefenamic Acid can also be used used for relief of mild to moderate pain including muscle pains and pain after injury, headaches and toothaches, period pains and pain following an operation or after childbirth, pain due to rheumatoid arthritis and osteoarthrosis. It is also used to treat excessively heavy periods caused by abnormal function and presence of a contraceptive coil, where the disease in the pelvis has been ruled out

Mefenamic acid can increase your risk of fatal heart attack or stroke, especially if you use it long term or take high doses, or if you have heart disease. Do not use this medicine just before or after heart bypass surgery (coronary artery bypass graft, or CABG).

Mefenamic acid may also cause stomach or intestinal bleeding, which can be fatal. These conditions can occur without warning while you are using mefenamic acid, especially in older adults.

You should not take mefenamic acid if you already have stomach bleeding or an active ulcer, or a bowel disorder such as ulcerative colitis, or if you have kidney disease.

How to use

Before you start the treatment, read the manufacturer’s printed information leaflet from inside the pack. It will give you more information about this acid, and it will also provide you with a full list of the side-effects which you could experience from taking it.
The usual dose is 500 mg, which is taken as two 250 mg capsules, or one 500 mg tablet. The usual dose is one 500mg three times each day for a maximum of three days, during one menstrual cycle.
For period pains, start taking your medicine when you first notice the pain.
As a general principle, the smallest effective dose should be used.
Take mefenamic acid with food. This will help to protect your stomach from side-effects such as indigestion.
The capsules should be swallowed whole with water. Do not chew them or break them.

Smoking and the consumption of alcohol is usually not advised as it may increase the side effects of the drug.

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Like all medicines Mefenamic Acid can cause side effects, although not everybody gets them.
All medicines can cause allergic reactions although serious

allergic reactions are rare. Any sudden wheeziness, difficulty in breathing, swelling of the eyelids, face or lips, rash or itching
(especially affecting your whole body) should be reported to a
doctor immediately.

Do not take if you have a peptic ulcer (ulcer in your stomach, or intestines) or bleeding in your stomach, or have had two or more
episodes of peptic ulcer, stomach bleeding or perforation.
STOP TAKING the medicine and tell your doctor if you experience:
• Indigestion or heart burn • Abdominal Pain (pains in your stomach) or other abdominal
(stomach) symptoms. If you suffer from any of the following at anytime during your treatment
STOP TAKING the medicine and see a doctor immediately.
• Pass blood in your stools/motions • Pass loose stool (Diarrhoea) • Pass black tarry stools • Vomit any blood or dark particles that look like coffee grounds.

Other Side Effects:
• Mouth ulcers, malaise, fatigue, unexplained bruising, fever or sore throat may occasionally occur, if you notice any of these symptoms speak to your doctor as they may be signs of a blood disorder • If a skin rash or jaundice (yellowing of the skin or whites of eyes) occur, tell your doctor • Nausea (feeling sick), vomiting (being sick), loss of appetite • Fits • Rapid heart beats • Reactions to the sun • You may notice urinary symptoms such as blood in the urine or an increase or decrease in the amount of urine, ankle swelling, reduced salt levels in the body • Symptoms such as sleep disturbance, depression, confusion, nervousness, hallucinations (imagining sensations), noise in the ears or impaired hearing, vertigo, dizziness, tingling or other odd sensations, problems with your eyesight or drowsiness have occasionally been reported • Symptoms of aseptic meningitis such as, over-reaction of the skin to sunlight, persistent headache, a stiff neck, fever, drowsiness or muscle pain may occur in some patients (especially in patients with existing auto immune disorders, such as systemic lupus erythematosus, mixed connective tissue disease) • Medicines such as mefenamic acid may be associated with a small
increased risk of heart attack (“myocardial infarction”) or stroke. Any risk is more likely with high doses and prolonged treatment. Do not exceed the recommended dose or duration of treatment. If you have heart problems, previous stroke or think that you might be at risk of
these conditions (for example if you have high blood pressure, diabetes or high cholesterol or are a smoker) you should discuss your treatment with your doctor or pharmacist

Further information can be found on the manufacturers
Paitient Information Leaflet and printed if required.