What is the treatment for a boil?

Treatment for Boils

For simple boils, incision and drainage is the primary and often sufficient treatment, with antibiotics reserved for specific high-risk situations. 1, 2

Primary Treatment Approach

Incision and Drainage

• Incision and drainage is the definitive treatment for large furuncles (boils) and all carbuncles, involving making an incision over the fluctuant area, thorough evacuation of pus, and probing the cavity to break up loculations 1, 2, 3
• Post-procedure wound care should involve simply covering the surgical site with a dry dressing—packing the wound with gauze causes more pain and does not improve healing 2, 3
• For simple abscesses or boils, incision and drainage alone is likely adequate without antibiotics 1

Small Boils

• For small furuncles, application of moist heat is satisfactory and may promote spontaneous drainage 2
• Warm compresses can help bring the boil to a head, allowing it to drain naturally 2

When to Add Antibiotic Therapy

Antibiotics should be added after incision and drainage in the following situations 1, 2:

• Severe or extensive disease (involving multiple sites of infection) or rapid progression with associated cellulitis 1
• Signs of systemic illness including fever >38°C, tachycardia >90 bpm, tachypnea >24 breaths/min, or abnormal white blood cell count 1, 2
• Associated comorbidities or immunosuppression (diabetes, HIV/AIDS, malignancy) 1
• Extremes of age (very young or elderly patients) 1
• Abscess in difficult-to-drain areas (face, hand, genitalia) 1
• Associated septic phlebitis 1
• Lack of response to incision and drainage alone 1

Antibiotic Selection When Indicated

For Suspected Methicillin-Susceptible Staphylococcus aureus (MSSA)

• Oral options: Dicloxacillin 250-500 mg every 6 hours or cephalexin 500 mg four times daily 1, 4
• Dicloxacillin should be taken on an empty stomach, at least 1 hour before or 2 hours after meals with at least 4 ounces of water 4

For Suspected Community-Associated MRSA (CA-MRSA)

Oral antibiotic options include 1:

• Clindamycin 300-450 mg three times daily (adults); 10-13 mg/kg/dose every 6-8 hours in children, not exceeding 40 mg/kg/day 1
• Trimethoprim-sulfamethoxazole (TMP-SMX) 1-2 double-strength tablets twice daily (adults); 4-6 mg/kg/dose of trimethoprim component every 12 hours in children 1
• Doxycycline 100 mg twice daily (adults); 2 mg/kg/dose every 12 hours in children >8 years 1
• Minocycline 200 mg once, then 100 mg twice daily (adults); 4 mg/kg once, then 2 mg/kg/dose every 12 hours in children 1

Duration of Therapy

• 5 to 10 days of antibiotic therapy is recommended when antibiotics are indicated 1
• Therapy should continue for at least 48 hours after the patient becomes afebrile and asymptomatic 4

Management of Recurrent Boils

For patients with recurrent boils, implement decolonization measures 2, 3:

• Daily chlorhexidine washes to reduce bacterial colonization 2, 3
• Intranasal mupirocin application 3
• Daily decontamination of personal items including towels, sheets, and clothing 2, 3
• Separate use of towels and washcloths 2, 3
• Thorough laundering of clothing and bedding 2, 3

Evaluation for Underlying Causes

• For recurrent abscesses at the same site, search for local causes such as pilonidal cyst, hidradenitis suppurativa, or foreign material 2
• Adult patients with recurrent abscesses beginning in early childhood should be evaluated for neutrophil disorders 2

Important Pitfalls to Avoid

• Do NOT use needle aspiration for boils—it has only 25% success rate overall and <10% with MRSA infections 2
• Do NOT pack wounds after incision and drainage—this causes more pain without improving healing 2, 3
• Do NOT use antibiotics as monotherapy for drainable abscesses without performing incision and drainage 1
• Do NOT attempt home lancing with non-sterile instruments—this can lead to severe invasive infections including osteomyelitis and sepsis 5
• Do NOT use rifampin as monotherapy or as adjunctive therapy for skin infections, as resistance develops rapidly and there is no proven benefit 1

Special Considerations

• Culture and sensitivity testing is recommended for carbuncles and recurrent cases, though treatment without cultures is reasonable for typical isolated cases 2
• Risk factors for recurrence include obesity, diabetes, age <30 years, smoking, and recent antibiotic use 6
• Approximately 10% of patients develop a repeat boil within 12 months 6