Part of the Access Doctor migraine treatment guide. Conditions overview: migraine & headache UK.
Migraine Triggers: What Causes Migraines & How to Identify Yours
A clinically reviewed guide to common migraine triggers — stress, sleep, hormones, diet, caffeine, alcohol — how to identify your personal triggers with a migraine diary, and how to manage them.
▶ Migraine triggers at a glance
A migraine trigger lowers the threshold for an attack in a genetically susceptible brain — it does not directly cause migraine. Most people have 3–4 personal triggers, and attacks often need multiple triggers to coincide. The most consistently evidenced triggers are stress, sleep disruption, hormonal changes, dehydration, and alcohol. Systematic diary-keeping is the best way to identify your individual pattern. GPhC pharmacy #9011198.
Triggers vs Causes
A trigger does not cause migraine — it provokes an attack in someone who is already neurologically susceptible. The underlying cause of migraine is a genetically determined hyperexcitability of the brain and trigeminovascular system. Triggers lower the threshold for an attack in a susceptible brain.
Most people with migraine have 3–4 identifiable triggers, and attacks often require multiple triggers coinciding. This is why the same trigger doesn't reliably cause an attack every time — the threshold effect means a combination pushes you over.
Common Migraine Triggers
| Trigger category | Examples | Notes |
|---|---|---|
| Stress | Work pressure, anxiety, emotional upset | Most consistently reported trigger. “Let-down” migraine (weekend migraine after work stress) is also common. |
| Sleep disruption | Too little or too much sleep; disrupted sleep schedule; jet lag | Both under- and over-sleeping can trigger. Consistent sleep/wake times are protective. |
| Hormonal changes | Menstruation (oestrogen withdrawal), ovulation, oral contraceptive pill changes | Menstrual migraine is particularly common and often more severe. See menstrual migraine guide. |
| Dehydration | Inadequate fluid intake; hot weather; exercise without hydration | One of the most modifiable triggers. Aim for consistent hydration throughout the day. |
| Skipped meals / fasting | Delayed breakfast; intermittent fasting; low blood sugar | Hypoglycaemia activates stress responses that can lower the migraine threshold. |
| Alcohol | Red wine, beer, spirits; any alcohol | Red wine and beer are more frequently implicated. Tyramine (in red wine) and histamine are possible mechanisms. |
| Caffeine | Caffeine withdrawal; large fluctuations in caffeine intake | Regular caffeine consumption itself is not a trigger; withdrawal is. Gradual reduction if cutting back. |
| Sensory stimuli | Bright or flickering lights, strong smells (perfume, chemicals), loud noise | Sensory triggers are often unavoidable in the environment; early treatment on unavoidable exposure helps. |
| Weather / barometric pressure | Pressure drops, storms, changes in temperature or humidity | Unmodifiable; awareness helps with anticipatory treatment. |
| Certain foods | Aged cheese (tyramine), processed meats (nitrates), MSG, chocolate | Food triggers are less consistently evidenced than commonly believed. Systematic elimination (not wholesale) is recommended. |
How to Identify Your Personal Triggers
Triggers are highly individual. A food that consistently triggers attacks in one person may be completely safe for another. The most reliable way to identify your personal triggers is a migraine diary.
A useful migraine diary records: date and time of attack onset · duration and severity · medications taken and response · potential trigger exposure in the preceding 24–48 hours (diet, sleep, stress, alcohol, menstrual cycle, weather) · number of headache days per month.
Trigger hunting pitfall: Craving chocolate or carbohydrates is a common prodrome symptom — part of the early migraine process, not a cause. If you eat chocolate and develop a migraine shortly after, the chocolate was not the trigger — the craving was a warning sign that an attack was already underway.
Managing Migraine Triggers
Not all triggers can be avoided. The approach is proportionate:
- Modifiable triggers (sleep regularity, hydration, meal timing, caffeine, alcohol): focus on these first as they yield the most benefit
- Unavoidable environmental triggers (bright lights, smells, weather): carry acute medication for prompt use
- Stress: regular exercise, mindfulness-based stress reduction, and adequate rest have evidence for migraine reduction
- Hormonal triggers: may respond to perimenstrual prophylaxis (naproxen or triptans taken around the period); see menstrual migraine guide
If attacks are frequent despite trigger management, preventive treatment may significantly reduce attack frequency — see migraine prevention.
Get Migraine Treatment Online
Prescription triptans, naproxen and preventive treatments from GPhC-registered pharmacist independent prescribers. Discreet next-day delivery. GPhC pharmacy #9011198.
View Migraine Treatments →Frequently Asked Questions
What are the most common migraine triggers?
The most consistently evidenced triggers are stress (especially let-down migraine), sleep disruption (too little or too much), hormonal changes (particularly menstrual oestrogen withdrawal), dehydration, skipped meals, alcohol, and sensory stimuli such as bright lights and strong smells. Triggers are highly individual.
Can chocolate trigger migraines?
The evidence that chocolate reliably triggers migraines is weak. Craving chocolate is a known prodrome symptom — part of the early migraine process. If you eat chocolate and develop a migraine, the craving may have been a warning that an attack was already beginning, not the chocolate itself causing it.
How do I find out what triggers my migraines?
Keep a migraine diary recording attack dates, severity, duration, medications used, and potential trigger exposures in the preceding 24–48 hours. After 2–3 months, patterns typically emerge. Avoid over-eliminating foods without evidence of a consistent link.
Can you become immune to your triggers?
No, but threshold management helps. Because attacks require multiple triggers, reducing background vulnerability (stress, sleep, hydration) can mean that a single trigger no longer reliably causes an attack. This is why lifestyle regularity has such a meaningful impact on attack frequency.
Should I try to avoid all migraine triggers?
Focus on modifiable triggers first — sleep regularity, hydration, meals, alcohol and caffeine. Environmental triggers (lights, smells) are less controllable — for these, having acute medication ready for early use is more practical than avoidance.
References
- NICE. Headaches in over 12s: diagnosis and management. CG150.
- Buse DC et al. Migraine triggers and treatment. Headache. 2012.
- NHS. Migraine. nhs.uk/conditions/migraine
Medical disclaimer: This article is for informational purposes only. Prescription migraine treatments require a clinical consultation. Always consult a qualified healthcare professional. In a medical emergency, call 999.