I take a prescription muscle relaxant the first day of my period...it's the only thing that keeps me sane. It actually helps prevent the cramping instead of just masking it. Also soaking in a hot bath helps more than just using heating pads.
You can also use dandellion to help relieve bloat, but you should start that a week before you expect your period along with watching your salt intake. A lot of women crave salty foods during pms which only aggrivates the situation.
My cycle is VERY irregular. As long as I take my BC properly I don't have any symptoms except a little cramping and a sore back. When I do get my period, I get wicked cramps the first few days!! It's brutal...I feel like someone is ripping out my insides! Hot baths and hot water bottles help, and I take either Midol or 600 mg Advil.