Antibiotic Selection for Patients with Multiple Drug Allergies and Moderate Renal Impairment

Introduction to Antibiotic Selection

The American Academy of Otolaryngology-Head and Neck Surgery recommends fluoroquinolones, such as levofloxacin or moxifloxacin, as the preferred first-line antibiotics for patients allergic to penicillin, sulfa drugs, and nitrofurantoin with an eGFR of 63 mL/min, with azithromycin or clarithromycin as alternative options depending on the infection type 1

Levofloxacin is an excellent choice for patients with multiple drug allergies, belonging to a completely different antibiotic class with no cross-reactivity concerns, and requires no dose adjustment with an eGFR of 63 mL/min for most infections 2
Moxifloxacin is also appropriate but carries a slightly higher anaphylaxis risk compared to levofloxacin 2
Azithromycin or clarithromycin are safe alternatives for penicillin-allergic patients with no structural similarity to beta-lactams, particularly useful for respiratory tract infections, and have excellent tissue penetration 3, 1

For respiratory tract infections, the first choice is levofloxacin 750 mg daily for 5 days, with azithromycin 500 mg day 1, then 250 mg daily for 4 days as an alternative 1
For urinary tract infections, levofloxacin 750 mg daily is recommended, and nitrofurantoin and trimethoprim-sulfamethoxazole should be avoided due to documented allergies 1

Cephalosporins should not be used without careful allergy history due to 1-3% cross-reactivity with penicillin allergies 1, 2
Trimethoprim-sulfamethoxazole should be avoided completely due to documented sulfa allergy 1
Tetracyclines or doxycycline should not be used as first-line in this patient given the safer alternatives available and potential for drug interactions 1
Nitrofurantoin should never be used due to documented allergy 1
QT interval should be monitored if macrolides are used with sertraline 3

Aminoglycosides, such as gentamicin or tobramycin, should be avoided despite no documented allergy, as they are nephrotoxic and inappropriate for non-severe infections in patients with any renal impairment 4