Migraines drive many people to take chances on more doctors and drugs than they can remember. The pain kept Shelia McMillan from playing games with her grandchild. The slightest sound or light hurt her.

"I would go back to the bedroom, turn all the lights out, black out curtains, and turn the ceiling fan on," said McMillan.

McMillan finally rolled the dice and turned to Botox. That's a medicine made from a bacteria that was approved in the early 1990s for treating certain eye and other problems. The Food and Drug Administration later approved Botox for injections into muscles to temporarily (about four months) smooth wrinkles.

"I was game for it, when you're at the end of the rope," said McMillan.

Dr. Roger Cady is studying Botox to relieve migraines.

"This is injected in the muscles under the skin. Typically, about 15 different sites are injected across the forehead, into areas above the eye and into the temples and around the back of the head," said Cady.

During a migraine, a brain chemical launches an army of signals to the brain. It causes the brain to shout "Pain, pain, pain!" Some doctors think Botox paralyzes the army and knocks out the invasion force.

"We are studying it and, ideally, the FDA will look at this and make a determination whether it's effective," said Cady.

McMillan doesn't need a ruling from the FDA to be convinced she's hit the lottery. Her migraines are rare now.

"When you go weekly with headaches and then you have weeks without headaches and then months, that's a good life," said McMillan.

The downside is insurance generally doesn't cover the cost of Botox, which can run about $1,000 a treatment and may need to be done every three to four months.