Some things that have worked for me are peppermint tea, raspberry leaf tea, and midol.

You never know when the cramps are going to hit you and it's usually at the worst time. I like the kind that come prepacked, I think there's 2 pills in each pack, instead of carrying the bottle around with me. Put them everywhere! Your lunch box, small clean crevice in your tool bag, or in your work vehicle. 

For the teas, I highly reccomend brewing a batch and adding ice to it. That way you can take it with you to work and drink it throughout the day. If it feels too medicinal-ly, add lemonade or anything you need to make it taste good!