What is the treatment for a boil?

Treatment for Boils

The primary treatment for a boil (furuncle) is incision and drainage, and antibiotics are generally not necessary for simple, uncomplicated boils. 1

Definition and Characteristics

• A boil (furuncle) is an infection of the hair follicle caused by Staphylococcus aureus, where suppuration extends through the dermis into the subcutaneous tissue, forming a small abscess 1
• Boils appear as inflammatory nodules with overlying pustules through which hair emerges 1
• Multiple adjacent infected follicles can coalesce to form a carbuncle, which is a larger, deeper inflammatory mass with pus draining from multiple follicular orifices 1

Treatment Algorithm

First-Line Treatment

1. Incision and drainage

   • This is the primary and most effective treatment for boils and abscesses 1
   • For small furuncles, application of moist heat may promote spontaneous drainage 1
   • Larger furuncles and all carbuncles require formal incision and drainage 1

2. Wound care after drainage

   • Simply covering the surgical site with a dry dressing is usually the easiest and most effective treatment 1
   • Packing the wound with gauze is not necessary and may cause more pain without improving healing 1

When to Consider Antibiotics

Antibiotics are not routinely needed for simple boils after adequate incision and drainage 1, but should be considered in the following situations:

• Presence of systemic inflammatory response syndrome (SIRS): temperature >38°C or <36°C, tachypnea >24 breaths/minute, tachycardia >90 beats/minute, or abnormal white blood cell count 1
• Severe or extensive disease involving multiple sites of infection 1
• Rapid progression with associated cellulitis 1
• Immunocompromised patients 1
• Extremes of age (very young or elderly) 1
• Boils in areas difficult to drain completely (face, hand, genitalia) 1
• Associated septic phlebitis 1
• Lack of response to incision and drainage alone 1

Antibiotic Selection When Indicated

For outpatients with purulent skin infections requiring antibiotics:

• First-line options (active against community-acquired MRSA):

  • Clindamycin: 300-450 mg PO TID 1
  • Trimethoprim-sulfamethoxazole (TMP-SMX): 1-2 DS tablets PO BID 1
  • Doxycycline: 100 mg PO BID 1
  • Minocycline: 200 mg × 1, then 100 mg PO BID 1

• For severe infections requiring intravenous therapy:

  • Vancomycin: 15-20 mg/kg/dose IV every 8-12 hours 1
  • Other options include linezolid, daptomycin, or ceftaroline 1

Management of Recurrent Boils

Approximately 10% of patients with boils will develop recurrent infections within 12 months 2. For recurrent boils:

1. Search for underlying causes:

   • Local factors: pilonidal cyst, hidradenitis suppurativa, or foreign material 1
   • Systemic factors: obesity, diabetes, smoking (all increase risk by approximately 30%) 2

2. Early drainage and culture of recurrent abscesses 1

3. Decolonization regimen for recurrent Staphylococcus aureus infections:

   • Intranasal mupirocin twice daily for 5 days 1
   • Daily chlorhexidine washes 1
   • Daily decontamination of personal items (towels, sheets, clothes) 1

4. Targeted antibiotic therapy:

   • 5-10 day course of antibiotics active against the cultured pathogen 1

Important Cautions

• Do not attempt home lancing of boils as this can lead to severe invasive infections 3
• Do not use ultrasonographically guided needle aspiration as it has low success rates, especially for MRSA infections 1
• Consider evaluation for neutrophil disorders in adults with recurrent abscesses that began in early childhood 1
• Mechanical stress and friction (e.g., from tight clothing) may contribute to recurrent boils in predisposed individuals 4

By following this evidence-based approach to boil management, focusing on appropriate drainage techniques and judicious use of antibiotics only when indicated, most patients will experience resolution with minimal complications.