Have you ever had headaches before? | ‘Yes’ suggests primary headaches more likely, although the patient may have more than one headache type |
Before the current episode, how many times a month (or a year) would you get a headache? | Patients with long-standing migraine are often undiagnosed and may discount their typical headaches as ‘normal headaches that everyone gets’ unless asked explicitly. Also ask about ‘menstrual headaches’ and ‘hungry headaches’ as a marker of migraine |
Is this your worst ever headache? | ‘Yes’ suggests secondary headaches more likely |
How long did the headache take to reach maximum intensity? | Possibly the most useful question. ‘Sudden onset’ is not sufficiently specific; ‘thunderclap’ headache should peak within 1 minute (at most 5 minutes); cluster headache develops over up to 30 minutes; migraine develops over hours |
What is the duration of headache? | Migraine and many secondary headaches are present from hours to days; headaches lasting minutes or those present for months or years tend to be more benign |
When did you last have a ‘crystal clear’ headache-free day? | A useful question in chronic headache (>15 days/month for >3 months), especially when initially reported to be constant |
When do you get the headaches? | Timing of attacks may be helpful – cluster headaches are commoner at night; morning headaches may be seen in obstructive sleep apnoea and raised intracranial pressure (ICP) |
Are there any triggers for the headache? | Eg stress, menstruation, diet, caffeine, alcohol, dehydration and other triggers are associated with migraine |
Do you have a warning before your headache? | Migraine may be heralded by a prodrome of loss of appetite, lethargy, drowsiness or difficulty concentrating in the hours before the headache |
| ∼30% have a true aura, lasting less than 60 minutes and includes more focal neurological symptoms such as visual scotoma or paraesthesia |
Where is the headache? | Location is not usually very helpful for diagnosis – most headache disorders may cause headache in any location |
| Strictly unilateral ‘side-locked’ headaches are characteristic of cluster headache and related disorders (trigeminal autonomic cephalalgias) but can also occur in migraine |
Associated features | |
Nausea or vomiting | Migraine or raised intracranial pressure (if severe vomiting always consider raised ICP) |
Blurred vision or visual loss | Migraine, acute angle-closure glaucoma or raised ICP |
Photophobia | Migraine, meningism, uveitis |
Phonophobia | Migraine |
Osmophobia |
Motion sensitivity / intolerance / aggravation by routine activity |
Restlessness / agitation | Cluster headache (contrast with the motion intolerance of migraine) |
Lacrimation | Trigeminal autonomic cephalalgias such as cluster headache, if unilateral; may also occur in migraine (bilateral or unilateral) |
Rhinorrhoea |
Conjunctival injection |
Visual obscurations (transient ‘graying out’ of vision for seconds, particularly on Valsalva manoeuvres) | Raised intracranial pressure |
Pulsatile tinnitus |
‘Red flag’ symptoms | See Table 2 ‘SNOOP4’ |