Do Not Use Expired Augmentin
You should not use Augmentin tablets that are 5 months past their expiration date. The clavulanate component degrades significantly after expiration, rendering the medication potentially ineffective and unsafe.
Why Expired Augmentin Is Problematic
Clavulanate Instability
The clavulanic acid component of Augmentin is chemically unstable and degrades rapidly, even under proper storage conditions. Research demonstrates that potassium clavulanate maintains only 90% of its concentration for approximately 2 days at room temperature 1. After 7 days at room temperature, clavulanate shows more than 40% degradation 1. While amoxicillin remains relatively stable, the loss of clavulanate means you're essentially taking amoxicillin alone—without the β-lactamase inhibitor that makes Augmentin effective against resistant bacteria.
Clinical Consequences of Degraded Medication
Using expired Augmentin creates two significant problems:
Treatment failure: Without adequate clavulanate, the medication cannot effectively treat β-lactamase-producing bacteria (common strains of H. influenzae, M. catarrhalis, and some S. aureus). This is particularly concerning for respiratory infections where these organisms are prevalent 2, 3.
Antimicrobial resistance: Taking subtherapeutic doses of antibiotics—which is what you get with degraded clavulanate—promotes bacterial resistance, a critical global health concern 4.
What You Should Do Instead
Obtain Fresh Medication
Contact your prescriber or pharmacist to obtain a new prescription. Most bacterial infections requiring Augmentin (sinusitis, otitis media, pneumonia, skin infections) need full-strength, properly formulated medication for optimal outcomes 3, 5, 6.
Storage Considerations for Future
The FDA label specifies proper storage requirements for Augmentin 7. Tablets should be stored according to manufacturer guidelines, and suspensions must be refrigerated with specific stability timeframes. Even when stored correctly, medications should never be used beyond their expiration dates.
Common Pitfall to Avoid
Do not assume that because the tablets "look fine" they retain their potency. Chemical degradation of clavulanate occurs regardless of visible changes to the tablet. The expiration date exists specifically because the manufacturer can only guarantee stability and efficacy until that date—beyond which the medication's therapeutic reliability cannot be assured.