A sweeping analysis of over 211 million supermarket receipts in England has uncovered a startling truth: many women may be reaching for the wrong painkiller to deal with period cramps. The study, published in PLoS Digital Health, examined a decade of loyalty card data from an unnamed high street chain and found that paracetamol was the most common painkiller purchased alongside tampons and sanitary towels - even though ibuprofen is likely more effective for muscle cramps.
The researchers, from Bristol and Nottingham universities, dug through purchases from 3.4 million shoppers between 2006 and 2015. Half of all menstrual product transactions also included a pain product, with about two-thirds being paracetamol-based and the rest ibuprofen. Paracetamol, the data suggests, may be the victim of its own popularity: it's a familiar name, good for headaches and fevers, but it works mainly in the brain to block pain signals. Ibuprofen, by contrast, blocks the production of prostaglandins - the chemicals that make uterine muscles contract and cramp in the first place.
Co-researcher Dr Anya Skatova from Bristol University called the data a "snapshot" rather than a fully representative national picture, but it still offers a rare look at how women actually manage period pain - a topic, the researchers note, that hasn't been studied much before. Investigator Prof James Goulding from Nottingham University put it more bluntly: "I don't think I'm going out on a limb here by saying that if men got period pain, we'd know a lot more about it by now."
For those looking to optimize their medicine cabinet, Endometriosis UK suggests starting ibuprofen the day before or several days before a period is expected, before the body cranks up prostaglandin production. The NHS warns that severe period pain could signal conditions like endometriosis or fibroids, so if cramps are stopping you from daily life, see a doctor. And as with any medication, check the packet - ibuprofen isn't for everyone, and side effects exist. But for most, the message is clear: when it comes to cramps, paracetamol might just be the wrong tool for the job.