Study: Women Often Buy Wrong Painkiller for Cramps

The two medicines work in different ways. Ibuprofen lowers prostaglandins — chemicals that make the womb muscle tighten and cause pain. So it can stop the pain at the start. Paracetamol works in the brain. It blocks pain signals and lowers fever, so it is good for headaches or flu. But it does not reduce swelling. Doctors suggest taking ibuprofen one day before a period begins. Researchers think people choose paracetamol because it feels more familiar.

The study also shows that period pain has not been studied enough. One researcher said that if men had period pain, we would know much more about it. Surveys suggest that seven in ten British women have bad period pain. Many have about three painful days each month. The NHS says women with very bad cramps should see a doctor.