A 34-year-old man presents to the emergency room with pain behind his eyes. He had a similar episode about 1 month ago which resolved after a few hours. The pain feels like a stabbing sensation behind his right eye. He denies any symptoms on the left side. The last time he had an episode like this, his eye was tearing. His temperature is 98.2°F (36.8°C), blood pressure is 120/90 mmHg, pulse is 110/min, and respirations are 12/min. Physical exam reveals a 2 mm pupil on the right and a 5 mm pupil on the left. Extraocular movements are intact bilaterally. The remainder of the neurologic exam is unremarkable. Which of the following is the most appropriate prophylactic treatment?
Sumatriptan
Verapamil
Ibuprofen
Propranolol
Verapamil
This patient with a history of retro-orbital pain, unilateral miosis (2 mm pupil on the right), and history of lacrimation during a similar episode is likely experiencing cluster headaches. Verapamil may be used as prophylaxis in the treatment of cluster headaches.

Cluster headaches occur more commonly in men and present with severe, unilateral, retro-orbital pain. Typical episodes last 15 minutes to 3 hours. Attacks may be associated with the circadian rhythm, as patients may notice that they get headaches at night. Because of the extreme pain, cluster headaches are sometimes colloquially referred to as "suicide" headaches. These headaches may present with autonomic symptoms, such as lacrimation and rhinorrhea. Horner syndrome may also occur, defined by a unilateral triad of ptosis, miosis, and anhidrosis. Acute management of cluster headaches includes administration of 100% oxygen. Other options include triptans. The first-line medication for prophylaxis of cluster headaches is verapamil. Studies have shown that lithium, topiramate, and ergotamine may also be effective as prophylaxis for cluster headaches; however, these therapies are less established than verapamil.

Blau and Engel review the use of medications for cluster headaches. They note that most of patients with episodic cluster headaches had complete suppression of attacks with the use of verapamil. It is recommended to give verapamil in this patient population.

Incorrect Answers:
Answer A: Ibuprofen is a non-steroidal anti-inflammatory drug (NSAID) that is used in the treatment of migraine and tension headaches. Migraine headaches present with unilateral, pulsating pain with photophobia and phonophobia, whereas tension headaches present with constant bilateral pain. Ibuprofen should not be used as prophylaxis for any type of headache as it has side effects including kidney dysfunction, ulcers, and even premature aging.

Answer B: Oxygen is first-line treatment for acute cluster headaches; however, it does not have any role in the prophylaxis of cluster headaches.

Answer C: Propranolol is a beta-blocker that is a prophylactic medication for migraine headaches. Migraines are more common in women and typically present as a unilateral headache with photophobia or phonophobia. They may also be associated with an aura, which presents as a visual, auditory, olfactory, or motor disturbance.

Answer D: Sumatriptan is a triptan that is used as an abortive treatment for migraine headaches and cluster headaches. It should not be used as prophylaxis for headaches.

Bullet Summary:
Verapamil may be used as prophylaxis for cluster headaches.