Migraines have stumped both doctors and scientists for years, while affecting the lives of millions of people.
No one has been able to work out what causes them or find an effective treatment.
But world first research has seen a breakthrough.
University of Sydney researchers have found a chemical imbalance of a substance called Gabba, common to everyone suffering the painful headaches.
“We don't know if it starts the pain, does it stop the pain, or is it just higher in people with migraine because of the long years that they've had it,” Researcher Maria said.
“We're excited about this finding because it adds a piece to the migraine puzzle and it improves understanding and it brings us closer to effective treatments for migraine.
The next step will be to conduct trials investigating why migraines afflict three times more women than men, and why some simply grow out of the condition.
It's welcome news for those struck down by them.
Many sufferers spend over $1000 a year in search of a solution. Their personal lives, families and careers all suffer because of these relentless headaches.
Marnee McKay is one of three million Australians dealing with the excruciating mystery.
“You'll notice that you're getting a headache, bright lights will start to irritate me,” she told 7 News.
“I start to walk a lit bit crooked, I'll start to feel quite nauseous”.
Miss McKay’s migraines started at four years old and happen about once a week.
It’s been 39 years of pain and no permanent fix.
“Oh I'd love a life without migraines, even my children know mummies headaches,” she said.
“I'm never very far away from any medication I might need to take, so to be free of that would be really liberating, it would be lovely”.
If you suffer migraines, don’t suffer in silence. Seek help from your GP.