About chronic migraine
Migraine attacks involve changes in brain activity and in the nerves and blood vessels around the brain. Some people experience aura, such as visual changes, before or during an attack. Migraine can shift from episodic to chronic over time, and overusing acute pain medications can contribute to more frequent headaches.
Common symptoms and challenges
- Moderate to severe, often one-sided or throbbing head pain
- Nausea or vomiting
- Sensitivity to light, sound or smells
- Aura, fatigue, neck pain and difficulty concentrating
- Triggers such as sleep changes, hormonal shifts, stress or skipped meals
Genetic and biological factors
Well established: Migraine runs strongly in families. Large studies have linked many genetic regions to migraine, each with a small effect. A few rare forms, such as familial hemiplegic migraine, are caused by single genes.
Mixed evidence: The MTHFR C677T variant has been studied in migraine with aura, with inconsistent results. It isn't used to diagnose or guide migraine treatment.
Laboratory testing
Migraine is diagnosed from your history and an examination. Imaging or blood tests are used only when a clinician suspects another cause.
Medication response
Some preventive medications, such as certain tricyclic antidepressants, are broken down by enzymes including CYP2D6 and CYP2C19, which are studied in pharmacogenetics.
Important limitations: No genetic test can diagnose migraine or predict which treatment will work for you. A pharmacogenetic result is something to discuss with your prescriber, not a reason to change medication on your own.
