Dysmenorrhoea, primary treatment

Clinical use Diflunisal (Brogden et al., 1980) is a nonsteroidal anti-inflammatory drug used in the treatment of mild to moderate pain including osteoarthritis, rheumatoid arthritis and primary dysmenorrhoea. It is used as base or lysine- or arginine-salt for oral or parenteral application. 

The symptoms described indicate primary dysmenorrhoea, so you could recommend treatment. Ibuprofen is the best analgesic to recommend, but check first that the girl is not sensitive to it. If ibuprofen is not effective after trying it for a couple of months she should see her doctor. 

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