From the FDA Drug Label
- Contraindications 4.1 Serious Hypersensitivity Reactions Amoxicillin and clavulanate potassium is contraindicated in patients with a history of serious hypersensitivity reactions (e.g., anaphylaxis or Stevens-Johnson syndrome) to amoxicillin, clavulanate or to other beta-lactam antibacterial drugs (e.g., penicillins and cephalosporins).
Amoxicillin-clavulanate (amox-clav) may not be reasonable for a patient sensitive to cloxacillin, as cloxacillin is a type of penicillin and amox-clav is also a beta-lactam antibacterial drug, which includes penicillins. The drug label states that amoxicillin-clavulanate is contraindicated in patients with a history of serious hypersensitivity reactions to other beta-lactam antibacterial drugs, such as penicillins 1.
- Key points:
- Hypersensitivity to penicillins (like cloxacillin) may cross-react with amox-clav.
- Amox-clav is contraindicated in patients with a history of serious hypersensitivity reactions to beta-lactam antibacterial drugs.
From the Research
For a patient with sensitivity to cloxacillin, amoxicillin-clavulanate (Augmentin) is not a reasonable option due to the potential for cross-reactivity, and alternative antibiotics such as cephalosporins or fluoroquinolones should be considered. When considering alternatives to amoxicillin-clavulanate for a patient sensitive to cloxacillin, it's essential to weigh the potential benefits and risks of each option.
- Cephalosporins, such as cefuroxime, may be suitable alternatives, but caution is warranted due to approximately 10% cross-reactivity between penicillins and cephalosporins, particularly first-generation cephalosporins 2.
- Fluoroquinolones, like levofloxacin (500-750 mg daily) or moxifloxacin (400 mg daily), are safer options for patients with severe penicillin allergies 3.
- Macrolides, such as azithromycin (500 mg on day 1, then 250 mg daily for 4 days), may also be considered depending on the infection being treated. The choice of alternative antibiotic ultimately depends on the specific infection, its severity, and the patient's allergy history. A detailed allergy assessment is crucial, as some patients with reported penicillin allergies may actually tolerate certain beta-lactams 4. The alternative antibiotic should provide similar coverage against the targeted pathogens that Augmentin would treat, including both gram-positive and gram-negative organisms, particularly beta-lactamase producing strains. It's also important to note that evidence-based research supports the use of prior research to inform new studies and ensure that research is worthwhile and valuable 5. In this case, the most recent and highest quality study 4 provides guidance on the use of amoxicillin and amoxicillin-clavulanic acid, highlighting the importance of considering the specific infection and patient factors when selecting an alternative antibiotic.