Antimicrobials USMLE Step 1 Practice Questions
55 board-style USMLE Step 1 questions in Pharmacology. Each question shows the correct answer; create a free account for the full explanation and adaptive practice.
- USMLE Step 1 · hard1. A 45-year-old man with a history of orthotopic lung transplantation 3 years ago presents to the hospital with a 2-week history of progressive dyspnea, fever, and nonproductive c…
- USMLE Step 1 · easy2. A 7-year-old boy with no prior antibiotic allergies presents with a 3-day history of acute otitis media and is started on amoxicillin-clavulanate. On day 3 of therapy, his mothe…
- USMLE Step 1 · hard3. A 55-year-old man with a 20-year history of chronic hepatitis C and compensated cirrhosis (Child-Pugh class A) develops a 4.2 cm hepatocellular carcinoma on surveillance imaging…
- USMLE Step 1 · hard4. A 19-year-old woman presents to the emergency department with fever (39.4°C), severe headache, neck stiffness, and photophobia. Vital signs show BP 116/74, HR 105, RR 22, SpO2 9…
- USMLE Step 1 · medium5. A 34-year-old woman without significant past medical history presents with a 3-day history of fever, dyspnea, and productive cough. She reports rust-colored sputum. Vital signs…
- USMLE Step 1 · hard6. A 62-year-old woman with gastroesophageal reflux disease takes daily omeprazole. She is prescribed clarithromycin for H. pylori eradication as part of triple therapy. After 5 da…
- USMLE Step 1 · medium7. A 45-year-old man with HIV infection and a CD4+ count of 180 cells/μL presents to the emergency department with a 4-day history of progressive dyspnea, nonproductive cough, and…
- USMLE Step 1 · medium8. A 28-year-old woman with no significant past medical history presents to the emergency department with a 12-hour history of fever, severe headache, and neck stiffness. Temperatu…
- USMLE Step 1 · medium9. A 72-year-old man with chronic kidney disease stage 3 (baseline creatinine 2.8 mg/dL, eGFR 22 mL/min/1.73m²) presents with fever, dysuria, and suprapubic pain for 3 days. Temper…
- USMLE Step 1 · medium10. A 67-year-old woman with atrial fibrillation presents with dysuria, frequency, and suprapubic pain. Vitals: BP 138/82, HR 92, RR 16, Temp 38.2°C, SpO2 98%. Urinalysis shows pyur…
- USMLE Step 1 · hard11. A 58-year-old man with no known drug allergies presents to the operating room for elective right inguinal hernia repair under general anesthesia. He receives cefazolin 1 g IV 30…
- USMLE Step 1 · medium12. A 41-year-old woman with severe inflammatory acne presents with BP 118/76, HR 82, RR 14, Temp 37.2°C. She is prescribed doxycycline 100 mg orally twice daily and currently takes…
- USMLE Step 1 · medium13. A 72-year-old man with a 20-pack-year smoking history and moderate-to-severe COPD presents with a 3-day history of worsening dyspnea, productive cough with purulent sputum, and…
- USMLE Step 1 · hard14. A 6-year-old boy presents with a 5-day history of otalgia, fever (38.9°C), and purulent ear drainage despite appropriate oral amoxicillin therapy (25 mg/kg/day divided twice dai…
- USMLE Step 1 · hard15. A 34-year-old man with HIV infection (CD4 count 175 cells/μL) presents with a 3-week history of productive cough, fever, and night sweats. Chest X-ray reveals bilateral upper lo…
- USMLE Step 1 · medium16. A 52-year-old woman with metastatic breast cancer on active chemotherapy presents to the hospital with fever (39.2°C), productive cough, and dyspnea for 3 days. She is immunocom…
- USMLE Step 1 · medium17. A 28-year-old man presents to the emergency department with a 2-day history of fever, severe headache, neck stiffness, and photophobia. Vital signs show temperature 39.8°C, bloo…
- USMLE Step 1 · medium18. A 45-year-old man with chronic kidney disease secondary to long-standing hypertension presents with fever, dysuria, and flank pain. His baseline eGFR is 25 mL/min and serum crea…
- USMLE Step 1 · medium19. A 32-year-old woman with no significant past medical history presents with community-acquired pneumonia characterized by fever (38.5°C), productive cough, and hypoxia (SpO2 92%…
- USMLE Step 1 · hard20. A 72-year-old woman with a CD4 count of 45 cells/μL presents to the emergency department with palpitations and dyspnea on exertion. She was started on azithromycin 1200 mg weekl…
- USMLE Step 1 · medium21. A 45-year-old man with a history of atrial fibrillation presents with a 3-week productive cough, night sweats, and 8-lb weight loss. Chest X-ray demonstrates a left upper lobe c…
- USMLE Step 1 · medium22. A 42-year-old man with community-acquired pneumonia is started on azithromycin. After 3 days, he develops severe watery diarrhea with abdominal cramping and fever (38.9°C). Vita…
- USMLE Step 1 · medium23. A 35-year-old man with HIV infection and a CD4 count of 45 cells/μL presents with a 5-day history of fever, severe headache, photophobia, and neck stiffness. Cerebrospinal fluid…
- USMLE Step 1 · hard24. A 78-year-old woman with a history of QT prolongation presents to the hospital with fever, cough, and infiltrates on chest X-ray consistent with healthcare-associated pneumonia.…