A 26-year-old man comes to the physician following an episode last night in which he awoke with a lancinating pain behind the right eye. He paced around his room for approximately 5 minutes and then the pain went away. He says his right pupil looked slightly smaller in the bathroom mirror during this episode. This is the third time such an episode has occurred during the past year, but he has always attributed it to stress. Physical examination shows no abnormalities. He is oriented to person, place, and time. Vitals are normal. Laboratory studies show no abnormalities. Which of the following is the most appropriate pharmacotherapy for this patient?
100% oxygen
Acyclovir
Carbamazepine
Gabapentin
Verapamil
