Australian researchers say they've worked out exactly what causes migraines.
They've pinpointed a hormone that triggers them and it's hoped the discovery will help them develop better drugs to treat the debilitating headaches.
Around 3 million Australians suffer from migraines, with nausea, dizziness, sharp pain and sensitivity to light all common symptoms.
Melbourne's Monash University has pinpointed the hormone responsible that latches onto the cells that cause the pain.
Chemists will use this research to create drugs to stop the pain, giving those suffering from migraines hope for some peace of mind.