Ponstan Forte Mefenamic acid 500 mg is a non-steroidal anti-inflammatory agent with analgesic properties, and a demonstrable antipyretic effect. It has been shown to inhibit prostaglandin activity. Suitable for 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 due to dysfunctional causes and presence of an IUD when other pelvic pathology has been ruled out. How to Use tablet (500mg) three times daily. A valid prescription should be available upon delivery