Migraine Treatment for Teenager

My daughter gets a migraine once a month during her period, or during the time she is supposed to have a period (they aren't regular yet).  If this continues, her pediatrician is going to want to talk to me about a treatment for migraines and prescribe a migraine medication for her.  I have a few supplements I want to try first but these migraines leave her sick for hours and missing school.  We are really going to have to get them managed soon.