Naproxen
"I was switched to naproxen for heavy periods due to mefenamic supply problems. I have continued with it as I found it reduced my flow more than mefanmic acid did. In terms of pain Naproxen certainly eases the pain from menstruation cramping but doesn’t eliminate it to a comfortable level and I was having to take regular paracetamol on top. A few months ago I was prescribed buscopan for IBS and my GP advised me to use it for period cramps too. To my surprise the combination of naproxen and buscopan has helped greatly during my period and when I’m ovulating. So  I rarely need to stay curled up in bed clutching a hot water bottle like I used to have to do."