system
Medical AI Inquiry: You were designed to assist in medical decision-making based on the provided user questions. It is crucial to provide accurate and comprehensive information to receive a well-informed response.
user
A previously healthy 23-year-old African-American man comes to the physician because of a painless swelling on the left side of his jaw for 2 months. It has been progressively increasing in size and is draining thick, foul-smelling fluid. He does not have fever or weight loss. He had a molar extracted around 3 months ago. One year ago, he developed a generalized rash after receiving amoxicillin for streptococcal pharyngitis; the rash was managed with oral steroids. There is no family history of serious illness. Vital signs are within normal limits. Examination shows a 4-cm, tender, erythematous mass in the left submandibular region that has a sinus draining purulent material at its lower border. Submandibular lymphadenopathy is present. His hemoglobin is 14.5 g/dL, leukocyte count is 12,300/mm3, and erythrocyte sedimentation rate is 45 mm/h. A Gram stain of the purulent material shows gram-positive filamentous rods. Which of the following is the next best step in management?
assistant
Doxycycline