I suffer migraines. Generally, I can predict them, I know what triggers them, and I can hold the symptoms at bay by sheer effort of will; self-trained biofeedback can work, although it's tiring. However, it's simpler to just let them burn themselves out; that way, they're pretty much over in a day, as opposed to leaving me suboptimal for several. Every medication for migraines I've tried has had side effects worse than just dosing up on powerful painkillers to reduce it to merely excruciating, lying back and watching the pretty lights and listening to the strange sounds (yes, I get full aura - even more so since I'm somewhat synaesthetic), so that's what I tend to do.
A while ago, I noticed that colas tended to be a trigger. Then I had a bottle of Gatorade... which triggered me. Turned out it had phosphoric acid in it... so now, that substance is banned from my diet. It's rust remover anyway.
Now, today, I tried a flavour of Gatorade I hadn't had before, and that has triggered me. It didn't have phosphoric acid in it.
I need to get health insurance so I can consult a doctor over this. It's getting silly.