A 25-year-old woman presents with a recurrent headache that is usually located around one eye, and she describes it as the "worst pain ever." The headaches usually occur at night and last for about an hour. During these episodes, her right eye becomes red and teary, and her right nostril becomes runny. What is the likely diagnosis and recommended treatment?
The patient's symptoms are characteristic of cluster headaches. These are severe, unilateral headaches that typically last between 15 minutes and 3 hours and can occur multiple times a day in clusters. First-line acute treatments include high-flow oxygen by face mask and sumatriptan. Preventative treatments such as verapamil or lithium may be considered in consultation with a neurologist.