What is the recommended treatment for a boil?

Treatment of Boils

The primary treatment for boils (furuncles) is incision and drainage, and antibiotics are usually not necessary for simple boils or abscesses. 1

Definition and Characteristics

• Boils (furuncles) are infections of hair follicles caused by Staphylococcus aureus, where suppuration extends through the dermis into subcutaneous tissue, forming a small abscess 1
• They appear as inflammatory nodules with overlying pustules through which hair emerges 1
• When infection extends to involve several adjacent follicles, producing a coalescent inflammatory mass with pus draining from multiple follicular orifices, it's called a carbuncle 1
• Carbuncles typically develop on the back of the neck and are more common in people with diabetes 1

Treatment Algorithm

For Small Furuncles:

1. Apply moist heat to promote drainage 1

   • Warm water compresses can be effective and inexpensive 2
   • Apply for 15-20 minutes several times daily

2. Keep the area clean to prevent spread of infection 1

   • Wash with mild soap and water
   • Cover with clean, dry dressing if needed

For Larger Furuncles and All Carbuncles:

1. Incision and drainage is the primary treatment 1

   • This involves making an incision, thoroughly evacuating the pus, and probing the cavity to break up loculations 1
   • Simply covering the surgical site with a dry dressing is usually the most effective treatment of the wound 1

2. Wound care after drainage:

   • Some clinicians pack the wound with gauze or close it with sutures, but evidence suggests packing may cause more pain without improving healing 1
   • Keep the area clean and dry 1

When to Consider Antibiotics:

Antibiotics are generally not recommended for simple boils or abscesses 1, but should be considered in the following situations:

1. Systemic signs of infection are present, such as:

   • Fever (temperature >38°C or <36°C) 1
   • Tachypnea (>24 breaths per minute) 1
   • Tachycardia (>90 beats per minute) 1
   • Abnormal white blood cell count (>12,000 or <400 cells/µL) 1

2. Other high-risk situations:

   • Immunocompromised patients 1
   • Extensive surrounding cellulitis 1
   • Multiple lesions 1
   • Markedly impaired host defenses 1
   • Incomplete source control 1

3. When antibiotics are needed, they should target Gram-positive bacteria, particularly S. aureus 1

   • Consider community-acquired MRSA coverage for patients at risk or who don't respond to first-line therapy 1

Management of Recurrent Boils

About 10% of patients with a boil or abscess develop a repeat infection within 12 months 3. For recurrent furunculosis:

1. Identify and address risk factors:

   • Obesity (RR 1.3) 3
   • Diabetes (RR 1.3) 3
   • Smoking (RR 1.3) 3
   • Young age <30 years (RR 1.2) 3
   • Prior antibiotic use (RR 1.4) 3

2. Decolonization measures for recurrent S. aureus infections 1:

   • 5-day regimen of intranasal mupirocin twice daily
   • Daily chlorhexidine washes
   • Daily decontamination of personal items (towels, sheets, clothes)

3. Improved hygiene measures 1:

   • Bathing with antibacterial soaps like chlorhexidine
   • Thorough laundering of clothing, towels, and bedding
   • Separate use of towels and washcloths

Important Cautions

• Do not attempt self-lancing of boils as this can lead to severe invasive infections 4
• Seek medical attention for boils that are large, extremely painful, accompanied by fever, or located on the face or spine 1
• Avoid friction from tight clothing which may contribute to boil development, especially in predisposed individuals 5
• Consider underlying conditions like hidradenitis suppurativa if boils are recurrent in typical locations (axillae, groin) 5

Special Considerations

• For patients with recurrent abscesses, search for local causes such as pilonidal cyst, hidradenitis suppurativa, or foreign material 1
• Adult patients with recurrent abscesses that began in early childhood should be evaluated for neutrophil disorders 1
• Gram stain and culture of pus from carbuncles and abscesses are recommended, but treatment without these studies is reasonable in typical cases 1