Not sure about antioxidants, but it's quite nice and uplifting. Tastes lovely with a splenda tablet thingy in it, yum! It's a bit tastier than peppermint tea, I think, i.e. you don't need as much sugar/sweetener for it to taste of something. Peppermint and spearmint are both good for stomach problems like IBS. Not sure about it helping with the pain and so on, but my fibro's pretty severe, so it may help if yours is a bit milder? I find that a lower carb diet helps quite a bit, so I'm sticking mainly to red days, don't know if you've tried that?