- if this is your first or worst ever headache
- if you have a headache with fever, stiff neck, nausea, vomiting, drowsiness or intolerance of light, especially following a head injury
- if you have a headache that has lasted several days, especially if there are other symptoms
- if you have a headache accompanied by altered vision or drowsiness
- if you have a headache for which self-help remedies haven’t worked in 3-7 days
- if you have a persistent one-sided headache with tenderness over the temples.
If you have other symptoms as well as problems with headaches, or a medical condition that seems to be worsening, it is important to see your doctor. Pain in the head or neck, from toothache, sinusitis or a blocked nose, can trigger an attack. If you take diabetic medicines, low blood sugar might bring on an attack. Very occasionally, being low in vitamin B12 can be a cause of migraine.
If you have recently started taking new medication, speak to your pharmacist about whether this might be the cause of your problems. Medications that can trigger migraine include ibuprofen (Nurofen) if overused, interferon-beta, GTN for angina, high doses of niacin (vitamin B3) or vitamin A (more than 25,000 IU daily).