What is the recommended dose and duration of oral antibiotics for the treatment of paronychia?

Treatment of Paronychia with Oral Antibiotics

For paronychia requiring oral antibiotic therapy, cephalexin 500mg four times daily for 7-10 days is the recommended first-line treatment. 1

Classification and Assessment

• Paronychia is inflammation of the tissue surrounding the nail fold that can be classified as acute (bacterial infection) or chronic (irritant dermatitis) 2
• Acute bacterial paronychia requires antibiotics when there are signs of significant infection including purulent discharge, spreading erythema, or systemic symptoms 3
• Chronic paronychia (symptoms lasting >6 weeks) represents an irritant dermatitis and typically does not require oral antibiotics unless secondary infection occurs 2

First-Line Oral Antibiotic Regimens

• Cephalexin 500mg four times daily for 7-10 days is the first-line treatment for infected paronychia, effective against common skin pathogens including Staphylococcus aureus and Streptococcus species 1
• Amoxicillin-clavulanate 875/125mg twice daily for 7-10 days provides broader coverage including anaerobes and beta-lactamase producing organisms when needed 1
• Clindamycin 300-450mg three times daily for 7-10 days is an appropriate alternative for penicillin-allergic patients 4
• Dicloxacillin 500mg four times daily for 7-10 days can be used when MSSA is the suspected pathogen 4

Treatment Algorithm Based on Severity

Mild Paronychia (Grade 1)

• Topical therapy is usually sufficient (povidone iodine 2%, topical antibiotics/corticosteroids) 4
• Oral antibiotics generally not needed unless signs of spreading infection 3

Moderate Paronychia (Grade 2)

• Continue topical therapy and add oral antibiotics if there is:
  • Pain with discharge or nail plate separation 4
  • Evidence of spreading infection 3
  • Failure to respond to topical therapy after 2 weeks 4

Severe Paronychia (Grade 3)

• Interrupt causative factors 4
• Obtain bacterial/fungal cultures 4
• Initiate oral antibiotics immediately 3
• Consider surgical drainage or partial nail avulsion for abscesses 4

Special Considerations

• For Candida-associated paronychia, oral fluconazole 100mg daily for 7-14 days may be needed when topical antifungals are insufficient 4
• For chronic paronychia, identify and eliminate irritant exposures rather than prolonged antibiotic therapy 2
• Systemic antibiotics should not be used routinely for paronychia associated with ingrown nails unless infection is proven 5

Adjunctive Measures

• Warm soaks with dilute povidone-iodine 2% solution twice daily 3
• Drainage is the most important intervention for paronychia with abscess formation 4
• Keeping the affected area dry is important for resolution 4

Follow-up Recommendations

• Re-evaluate after 2-3 days of antibiotic therapy to ensure improvement 1
• If no improvement after 48-72 hours, consider changing antibiotics based on culture results or adding surgical intervention 3