What is the best antibiotic treatment for an infected nail bed (paronychia)?

From the Guidelines

For infected nail bed (paronychia), the best antibiotic treatment is typically oral dicloxacillin 250-500 mg four times daily for 7-10 days, as recommended by the Infectious Diseases Society of America guidelines 1. This recommendation is based on the principle of targeting the most common causative organisms, Staphylococcus aureus and Streptococcus species.

• Alternatives to dicloxacillin include:
  • Cephalexin 500 mg four times daily
  • Amoxicillin-clavulanate 875/125 mg twice daily
  • Clindamycin 300-450 mg four times daily (for penicillin-allergic patients)
• Before starting antibiotics, drainage of any abscess is essential, and warm water soaks for 15 minutes 3-4 times daily can help reduce inflammation and pain.
• Topical antibiotics like mupirocin 2% ointment applied three times daily may be sufficient for very mild cases without systemic symptoms.
• For severe infections or those that don't respond to initial therapy, culture and sensitivity testing should guide antibiotic selection, and methicillin-resistant S. aureus (MRSA) coverage with trimethoprim-sulfamethoxazole or doxycycline may be necessary, as suggested by the Infectious Diseases Society of America guidelines 1.
• Patients with diabetes or immunocompromised conditions may require more aggressive treatment and closer monitoring, as recommended by the Infectious Diseases Society of America guidelines 1.

From the Research

Antibiotic Treatment for Infected Nail Bed (Paronychia)

• The best antibiotic treatment for an infected nail bed (paronychia) depends on the causative agent of the infection 2.
• Bacterial infections of the nails are caused by gram-negative bacteria, usually Pseudomonas aeruginosa, but also Klebsiella spp. and gram-positive bacteria like Staphylococcus aureus 2.
• Treatment of bacterial infections of the nail includes topical antiseptic agents (octenidine) and in some cases topical antibiotics (nadifloxacin, gentamicin) 2.
• Pseudomonas infections of the nail organ are treated with ciprofloxacin, while other bacteria are treated according to the results of culture and sensitivity testing 2.
• However, some studies suggest that antibiotics may be unnecessary after surgical drainage of uncomplicated skin and soft tissue abscesses caused by community strains of MRSA 3.

Fungal Infections of the Nail

• Fungal infections of the nail, including onychomycosis, are most frequently caused by fungi, primarily dermatophytes 2.
• Treatment of onychomycosis includes application of topical antifungal agents (amorolfine, ciclopirox) and oral treatment using terbinafine (in case of dermatophyte infection), fluconazole (for yeast infections), or alternatively itraconazole 2.
• Terbinafine has been shown to be effective in the treatment of Candida nail infection 4.
• Fluconazole has also been shown to be effective in the treatment of onychomycoses, with a recommended dosage of 200 mg once weekly for 4-6 months 5.

Treatment Considerations

• The choice of antibiotic or antifungal treatment for an infected nail bed should be based on the results of culture and sensitivity testing 2.
• Topical treatments may be sufficient for mild infections, while oral treatments may be necessary for more severe infections 2.
• The effectiveness of treatment should be monitored clinically and mycologically 4.