The painkillers will help reduce the pain once you have a headache. The opioid medications like vicodin and vicoprofin have an opioid along with another painkiller such as tylenol or ibuprofen. These can actually cause rebound headaches, so they are not a viable option long-term.

Amitriptyline and topamax are headache prevention medications (well, topamax actually is mainly used for seizures, but it's also used for migraine prevention). You take them every day (usually at bedtime), and over time they build up in your bloodstream and hopefully help you have headaches less frequently and less severely.

There is another class of medications like Imitrex that can be taken when a migraine is coming on. I think they work by affecting the blood flow to the head and/or brain. If taken when a headache first occurs, they are supposed to prevent it from getting worse.

Right now I am transitioning from amitriptyline to topamax, and I also have Imitrex for when I do get a headache, so I can hopefully stop it before it gets to be very bad.

Hope this helps!