Amoxicillin is Superior for Tooth Infections
For odontogenic (tooth) infections, amoxicillin is the clear first-line antibiotic choice, with clarithromycin and azithromycin reserved only for penicillin-allergic patients—though both macrolides have significantly higher failure rates (20-25%) and should be considered inferior alternatives. 1, 2, 3
Primary Treatment Principle
- Surgical intervention (drainage, debridement) is the cornerstone of treatment—antibiotics serve only as adjunctive therapy and should never be used alone 2, 3
- Antibiotics without adequate surgical management will fail regardless of which agent you choose 3
First-Line Recommendation: Amoxicillin
Amoxicillin 500 mg orally three times daily for 5 days is the gold standard for odontogenic infections 2, 3
Why Amoxicillin Wins:
- Broad spectrum coverage against the mixed oral flora (Streptococcus, Peptostreptococcus, Fusobacterium, Bacteroides, Actinomyces) that cause tooth infections 4, 5
- Low resistance rates compared to macrolides 5, 6
- Superior pharmacokinetic profile with excellent tissue penetration 5
- Safe, highly effective, and inexpensive 4
- Well-tolerated with minimal side effects 4
When to Escalate to Amoxicillin-Clavulanate
Upgrade to amoxicillin-clavulanate 875/125 mg twice daily for 5 days in these specific situations: 2, 3, 7
- Patient received amoxicillin in the previous 30 days 2
- Inadequate response to amoxicillin alone after 72 hours 2
- More severe infections with systemic involvement 2
- Diffuse swelling or cellulitis extending beyond the immediate site 3
The addition of clavulanate overcomes beta-lactamase producing strains that have proliferated in recent years 6
Macrolides: Clarithromycin and Azithromycin Are Inferior
Critical Limitations:
Both clarithromycin and azithromycin have predicted bacteriologic failure rates of 20-25% for odontogenic infections 8
- High resistance rates among oral streptococci—one study showed 41% erythromycin resistance, jumping to 82% after azithromycin treatment 8
- Should only be used in patients with true beta-lactam allergies (anaphylaxis, angioedema, urticaria) 8
- Not optimal coverage for the polymicrobial nature of tooth infections 8
If You Must Use a Macrolide:
- Reserve for documented Type I hypersensitivity reactions to penicillins 8
- Understand you're accepting a 20-25% higher failure rate 8
- Consider clindamycin 300-400 mg three times daily as a superior alternative for penicillin-allergic patients 3, 4
When Antibiotics Are Actually Indicated
Don't prescribe antibiotics reflexively. They're only needed when: 3
- Systemic involvement (fever, lymphadenopathy, malaise) 3
- Diffuse swelling or cellulitis extending beyond the extraction site 3
- Immunocompromised patients (diabetes, HIV, chemotherapy, chronic steroids) 3
- Progressive infection despite adequate surgical drainage 3
- Infections extending into cervicofacial tissues 3
For simple, localized abscesses in healthy patients with adequate surgical drainage, antibiotics provide no additional benefit 3
Common Pitfalls to Avoid
- Never prescribe antibiotics without surgical intervention—this is the most common error and guarantees treatment failure 2, 3
- Don't use prolonged courses—5 days is sufficient for most odontogenic infections 2, 3
- Don't confuse penicillin rash with true allergy—most patients with non-anaphylactic reactions can still receive amoxicillin 8
- Don't use fluoroquinolones (like levofloxacin) as first-line—they're not recommended for odontogenic infections and promote resistance 1
Clinical Algorithm
- Perform surgical drainage/debridement first (always) 2, 3
- Assess for systemic involvement or risk factors 3
- If antibiotics indicated:
- No recent antibiotics + no penicillin allergy → Amoxicillin 500 mg TID × 5 days 2, 3
- Recent amoxicillin use or severe infection → Amoxicillin-clavulanate 875/125 mg BID × 5 days 2, 3
- True penicillin allergy → Clindamycin 300-400 mg TID × 5 days (preferred over macrolides) 3, 4
- Cannot tolerate clindamycin → Clarithromycin or azithromycin (accept 20-25% failure rate) 8