Review Question - QID 108630

A 61-year-old woman presents to her primary care physician complaining of left-sided facial pain that started yesterday. She describes the pain as stinging, burning, and constant. It does not worsen with jaw movement or chewing. Her past medical history includes hyperlipidemia, multiple sclerosis, and childhood chickenpox. Medications include simvastatin and glatiramer acetate. The patient’s last MS flare was 5 weeks ago, at which time she received a prednisone burst with taper. At this visit, her temperature is 99.9 °F (37.7°C), blood pressure is 139/87 mmHg, pulse is 82/min, and respirations are 14/min. On exam, there is no rash or skin change visible on the patient’s face. Gentle palpation of the left cheek and mandible produces significant pain, but she has a full range of motion in the jaw. Which of the following medications is the most likely to prevent the long-term persistence of this patient’s pain?