I've got a couple of migraines already through this pregnancy, but didn't at all with my first pregnancy. I think it just depends on how your body is handling the pregnancy. When I went to my doc, he said that I can have certain drugs, at certain times during the pregnancy, but basically I can have panadeine forte at some period, and then mersyndol at others (mersyndol is great cos its a muscle relaxant too) and then only panadol at others. I would suggest that you have a stash of all different drugs, and if you feel one coming on, ring up a pharmacy and check which one falls into the category of drugs you can have at that time.
HTH!!!
Thanks for taking time to reply to my post Aricyn's Mum !

I should have mentioned that I have previously taken panadeine forte, mersyndol, inderal and something else that's name escapes me and none of these did anything to help (also taken Stemzine to try and stop the vomiting it rarely does). Perhaps these treatments would be more effective now I am pregnant ?

I am also worried about the effects of taking preventative medication or pain relief on my unborn child but am also worried if I don't take anything the way I feel and the amount of vomiting might also have a negative impact on my baby ? It's all so confusing.