Mefenamic acid reduces pain felt during menstruation by blocking a naturally occurring chemical called cyclo-oxygenase enzymes, which means the body produces fewer prostaglandins. Prostaglandins are chemicals that can cause pain and inflammation, especially at sites of injury. By reducing the production of prostaglandins, mefenamic acid helps to relieve pain and inflammation.
Like all medicines, this medicine can cause side effects, although not everybody gets them.
Possible side effects include:
- Digestive symptoms (stomach ache, indigestion, abdominal pain/discomfort, feeling/being sick, loss of appetite, diarrhoea or constipation)
- Sore mouth and/or lips
- Blood in the stools or urine
- Vertigo (head spinning)
- Blurred vision, eye irritation
- Ear pain, tinnitus (ringing in the ears)
- Dizziness, drowsiness, feeling lethargic and tired
- Depression
- Inability to sleep
If you experience these or any other side effects while taking this medicine seek advice from your doctor or pharmacist.
Do not take this medicine if you are allergic to any of the ingredients listed.
Please read the patient information leaflet before using this medicine.
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