A 33-year-old male arrives at the emergency department with complaints of dyspnea and productive cough that started a couple of days ago and have been getting progressively worse. His past medical history is significant for type 1 diabetes mellitus and hypertension. The patient reports drinking 3 beers per night and has a child in daycare that he thinks he got the sickness. The patient has NKDA and denies recent travel. The patient’s COVID-19 rapid antigen test is negative. The patient has a pulmonary infiltrate in the right lower lobe on his chest x-ray, which the medical resident confirms is consistent with community-acquired bacterial pneumonia (CABP). His baseline EKG reveals normal rate and rhythm with a QTc of 504 msec.  The medical resident in the emergency department calls the inpatient pharmacy to ask which medications that are appropriate in the treatment of CABP would adversely affect his QTc interval? (Select all that apply)

A. Levaquin

B. Cipro

C. Zosyn

D. Avelox

E. Vibramycin

F. Azithromycin

Answer with rationale:

The correct answers are A, D, and F.

Brand-Generics in this question: Levofloxacin (Levaquin), ciprofloxacin (Cipro), piperacillin/tazobactam (Zosyn), moxifloxacin (Avelox), doxycycline (Vibramycin), azithromycin (Zithromax).

This patient presents with symptoms and radiology consistent with community-acquired bacterial pneumonia(CABP). QTc prolongation is a common medication question directed at pharmacists. Numerous antimicrobials may prolong QTc which in combination with electrolyte abnormalities (e.g. hypokalemia, hypomagnesemia) may put the patient at risk for Torsades des Pointes, a potentially fatal arrhythmia. Fluoroquinolones and macrolides are the two classes of agents that are associated with QTc prolongation. Therefore answers A, D, and F are correct. Answer B while a fluoroquinolone is not appropriate for CABP as ciprofloxacin does not have dependable S. pneumoniae coverage which is a primary bacterial pathogen in CABP. The other listed agents do not significantly prolong QTc. In addition to medication regimen assessment, replacement of electrolytes (potassium +/- magnesium) is important to correct the abnormality.

Competencies covered:

2.2 – Commercial availability; prescription or non-prescription status; brand, generic, or biosimilar names; physical descriptions; or how supplied

3.7 – Adverse drug effects, toxicology, or overdose

3.11 – Evidence-based practice

 Have a great week!

Dr. B