Certain findings may serve as red flags of an underlying disorder causing a side-locked headache (secondary headache).

A side-locked headache is one that occurs > 90% of the time on one side of the head.


Secondary headaches:

(1) often are persistent and progressive

(2) may be precipitated by a provocative maneuver


Red Flag

May Indicate


temporal arteritis, malignancy, infection

weight loss

temporal arteritis, malignancy

cough or chest symptoms

lung cancer, infection

nasal or sinus symptoms



painful ophthalmoplegia syndrome

visual disturbance

glaucoma, ocular inflammation, optic neuritis, temporal arteritis, orbital lesion

cognitive, motor, sensory or cerebellar abnormality

intracranial lesion

pain peaks within minutes of onset

cervical artery dissection

new onset after 50 years of age

temporal arteritis, malignancy, glaucoma, cervicogenic headache


intracranial lesion


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