Problem: The nurse practitioner diagnoses a client, who has no known allergies, with sinusitis and prescribes which of the following antibiotics: Question Answer a. Trimethoprim-Sulfamethoxazole (TMP/SMX) double strength 800 mg/160 mg twice daily for 5 days b. Cephalexin 500 mg four times daily for 10 days c. Levofloxacin 500 mg twice daily for 5 days d. Amoxicillin 500 mg three times daily for 5 days