Contraindication: Augmentin Cannot Be Given to Patients with Penicillin Allergy
No, a 14-year-old girl with a documented penicillin allergy should NOT receive Augmentin (amoxicillin-clavulanate) 1g BID, as Augmentin contains amoxicillin, which is a penicillin-class antibiotic and is absolutely contraindicated in patients with penicillin allergy. 1, 2
Why Augmentin Is Contraindicated
- Augmentin is amoxicillin combined with clavulanate, making it a penicillin-based antibiotic that will trigger allergic reactions in patients with true penicillin allergy 3, 4
- Cross-reactivity is 100% within the penicillin class, meaning anyone allergic to penicillin will react to amoxicillin and all other penicillin derivatives 1, 5
- The risk includes potentially fatal anaphylaxis, particularly with IgE-mediated (Type I) hypersensitivity reactions 6, 1
Alternative Antibiotics for Penicillin-Allergic Patients
The choice of alternative depends on the severity and type of penicillin allergy:
For Non-Type I (Non-Immediate) Hypersensitivity:
- Second or third-generation cephalosporins are preferred: cefuroxime, cefdinir, or cefpodoxime 7
- Cross-reactivity risk is only 0.1% with these agents due to different chemical side chains 7, 5
- Cefazolin (first-generation) should be avoided as it has higher cross-reactivity 6
For Type I (Immediate/Severe) Hypersensitivity:
Dosing for a 14-Year-Old
Assuming average weight of 50kg for a 14-year-old:
- Azithromycin: 500mg PO daily for 5 days (or 10mg/kg on day 1, then 5mg/kg days 2-5) 6
- Clarithromycin: 250mg PO BID for 10 days (or 15mg/kg/day divided BID) 6
- Levofloxacin: 500-750mg PO daily (8-10mg/kg/dose daily for age >5 years) 6
- Clindamycin: 300-450mg PO QID or 25-40mg/kg/day IV divided TID 6
Critical Considerations Before Prescribing Alternatives
Verify the Allergy History:
- Only 1.98% of children reporting penicillin allergy are truly allergic when tested 8
- Document the type of reaction: rash, hives, angioedema, anaphylaxis, or timing (immediate vs. delayed) 8, 2
- Most reported allergies are not true IgE-mediated reactions 6, 5
Macrolide Limitations:
- >40% of Streptococcus pneumoniae is macrolide-resistant in many regions 7
- Reserve macrolides for true Type I allergy when fluoroquinolones cannot be used 7
Fluoroquinolone Cautions:
- FDA warnings exist for tendon rupture and other adverse effects, though these are acceptable in adolescents when penicillins are contraindicated 6, 7
- Should not be first-line in non-allergic patients 7
Common Pitfalls to Avoid
- Never assume "penicillin allergy" means all antibiotics are contraindicated—most patients can safely receive cephalosporins if the allergy is not Type I 7, 5
- Do not use trimethoprim-sulfamethoxazole as an alternative due to high resistance rates (50% for S. pneumoniae) 7
- Avoid first-generation cephalosporins (cephalexin, cefazolin) in any patient with penicillin allergy history 6, 7
- Consider allergy testing/delabeling if the patient requires frequent antibiotic therapy, as most reported allergies are not confirmed 6, 8