What oral antibiotics are used to treat paronychia?

Oral Antibiotics for Paronychia

Oral antibiotics are NOT first-line therapy for paronychia and should only be used for grade 2 or higher cases with suspected bacterial infection after obtaining cultures, or when topical therapy fails after 2 weeks. 1, 2

When to Use Oral Antibiotics

Reserve oral antibiotics for specific clinical scenarios:

• Grade 2 paronychia with suspected infection (nail fold edema/erythema with pain, discharge, or nail plate separation) 1
• Grade 3 or intolerable grade 2 cases requiring systemic therapy 1
• Treatment failure after 2 weeks of appropriate topical therapy 2, 3
• Presence of established abscess (though drainage is the most important intervention) 3

Always obtain bacterial/viral/fungal cultures before initiating oral antibiotics in grade 2 or higher cases. 1, 2

Recommended Oral Antibiotic Choices

For empirical therapy when infection is suspected:

• Amoxicillin/clavulanate - Recommended for pediatric patients, particularly those with oral self-soothing behaviors who are at risk for mixed anaerobic/aerobic infections 4
• Clindamycin - Alternative option for penicillin-allergic patients or mixed infections 4
• Oral cephalosporins - Have high in vitro activity against the majority of isolated organisms in EGFR inhibitor-associated paronychia 5
• Fluoroquinolones (ciprofloxacin, levofloxacin, or moxifloxacin) - Effective against most isolated microorganisms and achieve high tissue concentrations 5

Microbiological Considerations

The bacterial spectrum in paronychia includes:

• 72% Gram-positive bacteria (most commonly Staphylococcus aureus, including MRSA) 4, 5
• 23% Gram-negative bacteria 5
• 5% Candida species 5
• Mixed anaerobic/aerobic infections in children with finger-sucking habits 4

Critical Treatment Algorithm

Grade 1 (nail fold edema/erythema only):

• NO oral antibiotics needed 1
• Use topical povidone iodine 2% with topical antibiotics/corticosteroids 1, 2

Grade 2 (with pain, discharge, or nail separation):

• Obtain cultures if infection suspected 1, 2
• Continue topical therapy 1
• ADD oral antibiotics only if infection is suspected 1, 2
• Reassess after 2 weeks 1, 2

Grade 3 (surgical intervention indicated):

• Interrupt causative drug until grade 0-1 1
• Obtain cultures 1
• Oral antibiotics AND/OR surgical drainage 1
• Consider partial nail avulsion 1, 3

Important Caveats

Avoid these common pitfalls:

• Do not use systemic antibiotics routinely without proven infection 6
• Oral antibiotics are usually not needed if adequate drainage is achieved, unless the patient is immunocompromised 7
• For drug-induced paronychia (EGFR inhibitors, chemotherapy), recognize this is primarily an inflammatory process, not primary infection - secondary infection occurs in only 25% of cases 2
• Avoid topical steroids if purulent drainage is present until infection is adequately treated 2

For Candida-associated paronychia: Use topical imidazole lotions as first-line; oral itraconazole 200 mg daily (or pulse 400 mg daily for 1 week per month for 2-4 months) only for nail plate invasion 3