What is the recommended dose of penicillin (Penicillin V potassium) for a tooth infection?

Penicillin VK Dosing for Tooth Infections

For dental infections in adults, penicillin VK 500 mg four times daily (every 6 hours) for 7-10 days is the recommended dose when antibiotics are indicated. 1

When Antibiotics Are Actually Indicated

The critical caveat is that antibiotics should NOT be routinely prescribed for most dental infections 2, 3. The evidence is clear on this:

• For acute dental abscesses and apical periodontitis, surgical treatment (drainage, root canal therapy, or extraction) is the primary treatment—antibiotics alone are ineffective 2, 3
• Antibiotics are only indicated as adjunctive therapy when there is evidence of systemic spread: fever, malaise, lymphadenopathy, cellulitis, or diffuse swelling extending beyond the local area 2, 3
• For localized dental abscesses without systemic signs, incision and drainage or definitive dental treatment alone is sufficient 2

Specific Dosing Recommendations

When antibiotics ARE indicated for dental infections:

First-Line Treatment (Non-Penicillin Allergic)

• Penicillin VK: 500 mg orally four times daily (every 6 hours) for 7-10 days 1
• Alternative: Amoxicillin 500 mg three times daily for 7-10 days 2, 1

For Penicillin-Allergic Patients

• Clindamycin 300-450 mg orally three times daily 2
• This provides coverage for both streptococci and anaerobes commonly found in dental infections 2

For Severe Infections or Treatment Failures

• Amoxicillin-clavulanate (Augmentin) 875/125 mg twice daily 2
• This covers penicillinase-producing organisms and anaerobes 2

Critical Clinical Pitfalls

Do NOT prescribe antibiotics for:

• Irreversible pulpitis without systemic signs - penicillin provides no pain relief and is completely ineffective 4
• Localized dental abscesses that can be drained - surgical drainage is definitive treatment 2, 3
• Chronic periodontitis - antibiotics are not indicated 2

The evidence shows that when antibiotics are given WITH surgical intervention (drainage, endodontic treatment), they provide no additional benefit for pain or swelling reduction compared to surgical treatment alone 3. This reinforces that the surgical intervention is the essential treatment.

Duration and Follow-Up

• Standard duration is 7-10 days 1, 2
• If no improvement within 2-3 days despite appropriate surgical treatment, consider second-line agents (amoxicillin-clavulanate, clindamycin) or re-evaluate for inadequate source control 5
• Patients should be instructed that definitive dental treatment (root canal or extraction) must be completed—antibiotics are only a temporizing measure 2, 3