What antibiotics are recommended for treating paronychia?

Antibiotic Treatment for Paronychia

First-Line Antibiotic Recommendations

For acute bacterial paronychia, dicloxacillin (250 mg 4 times daily) or cephalexin (250 mg 4 times daily) are the recommended first-line oral antibiotics, targeting Staphylococcus aureus as the primary pathogen. 1

Alternative Regimens for Specific Situations

Penicillin-allergic patients:

• Clindamycin 300-400 mg three times daily is the preferred alternative 1
• Note: Cephalosporins are contraindicated in patients with immediate penicillin hypersensitivity (urticaria, angioedema, bronchospasm, or anaphylaxis) 2

Suspected or confirmed MRSA infection:

• Trimethoprim-sulfamethoxazole (1-2 double-strength tablets twice daily) 1
• Doxycycline (100 mg twice daily) 1
• For community-acquired non-multiresistant MRSA, clindamycin or lincomycin are also appropriate choices 2

Pediatric patients with oral self-soothing behaviors:

• Broad-spectrum coverage with amoxicillin-clavulanate or clindamycin is suggested due to risk of mixed anaerobic and aerobic infections 3

When Antibiotics Are NOT Indicated

Systemic antibiotics should not be used routinely for paronychia, particularly when associated with ingrown toenails, unless infection is proven. 4 The key distinction is:

• Acute bacterial paronychia with purulent drainage: Antibiotics indicated after drainage 5
• Chronic paronychia (≥6 weeks duration): This is an irritant dermatitis, not primarily infectious—topical steroids are preferred over antibiotics 1, 5
• Paronychia with ingrown toenail but no infection: Antibiotics are ineffective; address the mechanical problem 4

Treatment Algorithm Based on Clinical Presentation

Mild Acute Paronychia (No Abscess)

• Warm soaks with dilute vinegar (50:50 dilution) or 2% povidone-iodine for 10-15 minutes twice daily 1, 5
• Topical antibiotics with or without topical steroids 5
• Oral antibiotics usually not needed if no abscess present 5

Moderate Acute Paronychia (Abscess Present)

• Drainage is mandatory—various techniques from needle instrumentation to scalpel incision 5, 6
• After adequate drainage, oral antibiotics typically not required unless patient is immunocompromised or severe infection present 5
• If antibiotics needed: dicloxacillin or cephalexin as first-line 1

Severe or Immunocompromised Patients

• Obtain cultures before initiating antibiotics if purulent drainage present 1
• Start empiric therapy with dicloxacillin or cephalexin 1
• Adjust based on culture results and local resistance patterns 1

Chronic Paronychia (≥6 Weeks)

• Mid- to high-potency topical steroids are first-line, NOT antibiotics 1, 5
• Topical povidone-iodine 2% twice daily has demonstrated benefit 1
• If Candida confirmed on culture: itraconazole first-line, fluconazole as alternative 1
• Address underlying irritant exposure (chemicals, water, trauma) 5

Critical Clinical Pitfalls to Avoid

Do not prescribe systemic antibiotics reflexively—up to 25% of paronychia cases have secondary bacterial or fungal superinfections, but many cases are inflammatory rather than infectious. 4, 5

Stop topical steroids immediately if purulent drainage develops, as steroids worsen active infection. 1

Recognize drug-induced paronychia (particularly from EGFR inhibitors in cancer patients), which requires different management approaches and will not respond to antibiotics. 1

Culture-guided therapy is essential in treatment failures—adjust antibiotics based on sensitivity patterns rather than empirically escalating coverage. 1

Adjunctive Measures

Regardless of antibiotic use, implement these supportive measures:

• Antiseptic soaks with dilute vinegar or 2% povidone-iodine 1
• Avoid repeated trauma to the nail unit 1
• Wear comfortable, well-fitting shoes 1
• Trim nails straight across, not too short 1