What is the best antibiotic for treating paronychia?

Best Antibiotic for Paronychia

For acute bacterial paronychia, dicloxacillin 250 mg four times daily or cephalexin 250 mg four times daily are the first-line antibiotics, targeting Staphylococcus aureus. 1

Acute Bacterial Paronychia

First-Line Antibiotic Therapy

• Dicloxacillin 250 mg four times daily is the preferred first-line agent for acute bacterial paronychia 1
• Cephalexin 250 mg four times daily is an equally effective alternative first-line option 1
• Both agents target Staphylococcus aureus, the most common causative organism in acute bacterial paronychia 2, 3

Penicillin-Allergic Patients

• Clindamycin 300-400 mg three times daily is recommended for patients with penicillin allergy 1

MRSA Coverage

• Trimethoprim-sulfamethoxazole (1-2 double-strength tablets twice daily) should be used when MRSA is suspected 1
• Doxycycline 100 mg twice daily is an alternative for suspected MRSA infection 1

Critical Treatment Principles

• Antibiotics are only indicated after adequate drainage is achieved or when drainage alone is insufficient 2, 3
• Oral antibiotics are usually unnecessary if adequate abscess drainage is performed, unless the patient is immunocompromised or severe infection is present 2
• Warm soaks with or without Burow solution or 1% acetic acid should be the initial treatment approach 2
• The presence of an abscess mandates drainage, which can range from needle instrumentation to scalpel incision 2

Culture-Guided Therapy

• Culture-guided therapy should be considered in treatment failures, with antibiotic adjustment based on sensitivity patterns 1
• Acute paronychia is caused by polymicrobial infections after the protective nail barrier has been breached 2

Chronic Paronychia

Non-Antibiotic First-Line Treatment

• Topical steroids (mid to high potency) are preferred for chronic paronychia, as this represents an irritant dermatitis rather than an infection 1, 2
• Topical povidone iodine 2% twice daily has demonstrated benefit in controlled studies 1
• Chronic paronychia is characterized by symptoms lasting at least six weeks and represents an irritant dermatitis to the breached nail barrier 2

Fungal Infection Management

• If Candida is confirmed, itraconazole should be considered first-line treatment, with fluconazole as an alternative 1
• Bacterial or mycological infections in chronic paronychia are typically secondary colonizations, not primary causes 4
• In severe candidiasis of the nails, oral fluconazole 100 mg for 20 days can be added to topical therapy 5

Common Pitfall

• Do not use systemic antibiotics routinely for chronic paronychia unless infection is proven 4
• Chronic paronychia is frequently non-infective, though chronically irritated tissue may become secondarily colonized by fungi 3

Adjunctive Measures

• Antiseptic soaks with dilute vinegar or 2% povidone-iodine are recommended as adjunctive measures 1
• Avoidance of repeated trauma to the nail unit is essential 1
• Patient education is paramount to reduce recurrence of both acute and chronic paronychia 2

Special Considerations

• Drug-induced paronychia, particularly from EGFR inhibitors in cancer patients, requires different treatment approaches and should not be treated with standard antibiotics 1
• Paronychia is a frequent side-effect of chemotherapies and targeted therapies 4
• Patients with chronic paronychia unresponsive to standard treatment should be investigated for unusual causes, such as malignancy 3