Don't miss

• Subarachnoid hemorrhage
• Meningitis
• Temporal (giant cell) arteritis
• Glaucoma
• Hypertension
• Cerebral ischemia
• Arterial dissection (carotid or vertebral)
• Brain tumor

Intracranial

• Migraine
• Cluster headache
• Subarachnoid hemorrhage
• Meningitis
• Brain abscess
• Temporal (giant cell) arteritis
• Hypertension
• Caffeine, alcohol, or drug withdrawal
• Pseudotumor cerebri
• Subdural hemorrhage
• Cerebral ischemia
• Arterial dissection (carotid or vertebral)
• Arteriovenous malformation
• Head injury
• Neurocysticercosis
• Venous sinus thrombosis (intracranial venous thrombosis)
• Post-lumbar puncture
• Carbon monoxide poisoning
• Preeclampsia

Extracranial

• Tension headache
• Sinusitis
• Cervical arthritis
• Glaucoma
• Refractive error
• Dental abscess
• Otitis media
• Temporomandibular joint syndrome
• Depression
• Somatoform disorder (eg, somatization)
• Trigeminal neuralgia
• Glossopharyngeal neuralgia

• Facial, tooth, or jaw pain