What is the recommended antibiotic treatment for a patient with paronychia, considering their medical history and potential allergies?

Antibiotic Treatment for Paronychia

For acute paronychia with suspected bacterial infection, oral antibiotics targeting Staphylococcus aureus and Streptococcus (such as dicloxacillin, cephalosporins, or fluoroquinolones) should be prescribed only after adequate drainage is achieved, unless the patient is immunocompromised or has severe infection. 1, 2

Treatment Algorithm Based on Severity

Grade 1 (Mild) Paronychia

• Continue current activities and apply topical therapy first 3, 1
• Apply topical povidone iodine 2% daily to the affected area 3, 1
• Use topical antibiotics combined with corticosteroids 3, 1
• Implement warm water soaks for 15 minutes, 3-4 times daily, or white vinegar soaks (1:1 dilution) for 15 minutes daily 3, 4
• Oral antibiotics are NOT indicated at this stage 2, 5
• Reassess after 2 weeks; if no improvement, escalate to Grade 2 treatment 3, 4

Grade 2 (Moderate) Paronychia

• Obtain bacterial/viral/fungal cultures if infection is suspected 3
• Continue topical povidone iodine 2% 3, 1
• Apply mid-to-high potency topical corticosteroid ointment to nail folds twice daily 4
• Initiate oral antibiotics if infection is confirmed or suspected 3
  • First-line options: Dicloxacillin, cephalosporins (high activity against isolated organisms) 6
  • Alternative options: Ciprofloxacin, levofloxacin, or moxifloxacin (broad coverage with high tissue penetration) 6
• Consider dose reduction or interruption of causative medications (if drug-induced) 3
• Reassess after 2 weeks 3, 4

Grade 3 (Severe) Paronychia

• Drainage is mandatory for established abscess—this is the most important intervention 1, 2
• Drainage options range from needle instrumentation to wide incision with scalpel 1, 7
• Obtain cultures before initiating antibiotics 3
• Prescribe oral antibiotics based on culture results and local resistance patterns 2, 6
• Consider partial nail avulsion for intolerable cases with pyogenic granuloma 1, 4
• Interrupt causative medications until resolved to Grade 2 3

Special Considerations for Candida-Associated Paronychia

Up to 25% of paronychia cases develop secondary Candida superinfection 4, 2

• First-line: Topical imidazole lotions (azoles or polyenes) 1, 4
• For nail plate invasion or severe cases: Oral itraconazole 200 mg daily or pulse therapy (400 mg daily for 1 week per month) for minimum 4 weeks (fingernails) or 12 weeks (toenails) 3, 1, 4
• Alternative: Oral fluconazole 50 mg daily or 300 mg weekly for minimum 4 weeks 3, 4
• Avoid terbinafine—it has limited and unpredictable activity against Candida 1
• Keep affected area dry, as moisture promotes candidal growth 4

Antibiotic Selection Based on Microbiology

Microbiological analysis of paronychia reveals 72% Gram-positive bacteria, 23% Gram-negative bacteria, and 5% Candida species 6

Empirical Oral Antibiotic Choices:

• Cephalosporins (high in vitro activity against majority of isolated organisms) 6
• Fluoroquinolones (ciprofloxacin, levofloxacin, moxifloxacin)—achieve high tissue concentrations 6
• Dicloxacillin (for confirmed Staphylococcus aureus or Streptococcus) 8, 6
• Clarithromycin 500 mg twice daily for 6 days (for bacterial perionyxis) 9

Important Antibiotic Considerations:

• Screen for penicillin allergy before prescribing dicloxacillin—serious anaphylactic reactions occur in 0.015-0.04% of patients 8
• Patients with penicillin hypersensitivity may cross-react with cephalosporins 8
• Monitor for Clostridium difficile-associated diarrhea (CDAD)—can occur up to 2 months after antibiotic use 8

Common Pitfalls to Avoid

• Do NOT use systemic antibiotics routinely without proven infection—paronychia is often inflammatory, not infectious 5, 7
• Do NOT rely on oral antibiotics alone if abscess is present—drainage is mandatory 1, 2
• Do NOT prescribe antibiotics for ingrown toenail-associated paronychia unless infection is proven 5, 7
• Do NOT overlook secondary fungal colonization in chronic cases—up to 25% have Candida superinfection 4, 2
• Do NOT use terbinafine for Candida-associated paronychia—it is ineffective 1
• Do NOT ignore drug-induced paronychia (EGFR inhibitors, chemotherapy)—requires specific management with dose modification 3, 5

Prevention Strategies

• Keep hands and feet dry; avoid prolonged soaking in soapy water 3, 4
• Wear protective gloves during wet work 4, 2
• Trim nails straight across; avoid cutting too short or nail biting 3, 4
• Apply emollients daily to cuticles and periungual tissues 3, 4
• Avoid nail trauma and restrictive footwear 3