What antibiotic is recommended for a tooth infection?

Antibiotic Treatment for Tooth Infections

For most tooth infections, surgical intervention (drainage, root canal, or extraction) is the primary treatment, and antibiotics should only be added when there is systemic involvement (fever, malaise), spreading infection (cellulitis, diffuse swelling), or the patient is immunocompromised. 1

Primary Treatment Approach

Surgical management is the cornerstone of treatment and should never be delayed. 1 The evidence consistently demonstrates that:

• Root canal therapy or extraction of the affected tooth is the definitive treatment for acute dental abscesses 1
• Incision and drainage is the first step for dentoalveolar abscesses 1
• Multiple systematic reviews show no statistically significant differences in pain or swelling outcomes when antibiotics are added to surgical treatment alone 1

When Antibiotics Are Indicated

Antibiotics should be prescribed only in specific clinical scenarios:

• Systemic symptoms present: fever, malaise, or other signs of systemic involvement 1
• Spreading infection: evidence of cellulitis or diffuse swelling beyond the localized area 1
• Immunocompromised patients: those with systemic diseases affecting immunity or localized defense defects 1, 2
• Medically complex patients: those with prosthetic cardiac valves, recent prosthetic joint replacement, or risk of infective endocarditis 2
• Progressive infections: cases requiring referral to oral surgeons 1

First-Line Antibiotic Selection

When antibiotics are indicated, phenoxymethylpenicillin (Penicillin V) or amoxicillin for 5 days is the first-choice treatment. 1, 3

Rationale for First-Line Choice:

• Penicillin V remains highly effective against typical odontogenic pathogens (Streptococcus, Peptostreptococcus, Fusobacterium, Bacteroides species) 4, 5
• Amoxicillin is recommended due to better absorption and lower risk of side effects compared to Penicillin V 2
• Both agents are safe, inexpensive, and have a narrow microbiologic spectrum 4

Dosing:

• Adults: Amoxicillin 500 mg three times daily or phenoxymethylpenicillin 500 mg four times daily 3
• Pediatric: Amoxicillin 90 mg/kg/day divided in 2-3 doses 3

Second-Line Treatment Options

For Penicillin-Allergic Patients:

Clindamycin is the antibiotic of choice for patients with confirmed penicillin allergy. 1, 2

• Adult dosing: 300-450 mg orally three times daily 1
• Pediatric dosing: 10-20 mg/kg/day in 3 divided doses 1
• Clindamycin is very effective against all odontogenic pathogens 4

For Treatment Failures:

If the initial antibiotic fails after 48-72 hours, add metronidazole to amoxicillin or switch to amoxicillin-clavulanate. 1, 3

• Amoxicillin-clavulanate: 875/125 mg twice daily for adults 1
• Pediatric amoxicillin-clavulanate: 90 mg/kg/day (of amoxicillin component) divided twice daily 1
• This combination provides enhanced anaerobic coverage and protection against beta-lactamase producing organisms 1

Treatment Duration

Maximum antibiotic duration should be 5-7 days with adequate source control. 1

• The WHO recommends a maximum of 7 days for immunocompromised or critically ill patients 1
• Total duration of 5-10 days based on clinical response 1

Severe Infections Requiring IV Therapy

For severe infections with systemic toxicity or deep tissue involvement:

• First choice: Clindamycin 600-900 mg IV every 6-8 hours (pediatric: 10-13 mg/kg/dose IV every 6-8 hours) 1
• Alternative regimens: Piperacillin-tazobactam 3.375g every 6 hours IV, or ceftriaxone 1g every 24 hours IV plus metronidazole 500 mg every 8 hours IV 1
• Transition to oral therapy (clindamycin 300-450 mg three times daily) when clinically improved 1

Common Pitfalls to Avoid

Do not prescribe antibiotics for:

• Symptomatic irreversible pulpitis 2
• Necrotic pulps without systemic involvement 2
• Localized acute apical abscesses that can be drained 2, 1

Avoid these agents for routine dental infections:

• Fluoroquinolones are inadequate for typical dental abscess pathogens 1
• Metronidazole alone is insufficient as it lacks coverage against facultative and anaerobic gram-positive cocci 4
• Tetracyclines have limited role due to high incidence of gastrointestinal disturbances and superinfection 4
• Erythromycin and other macrolides have higher failure rates (20-25% bacteriologic failure) 3

Special Considerations

For infections extending into cervicofacial tissues, more aggressive management is required, including tooth extraction and treatment as necrotizing fasciitis 1

MRSA coverage is not routinely indicated in initial empiric therapy of dental abscesses based on current data 1