Treatment of Skin Boils
Incision and drainage is the definitive treatment for skin boils (furuncles), with systemic antibiotics reserved only for specific complicated cases. 1
Primary Treatment Approach
Incision and Drainage (I&D)
- I&D is the cornerstone of treatment for large furuncles, involving making an incision over the fluctuant area, thorough evacuation of pus, and probing the cavity to break up loculations. 1
- Multiple counter incisions should be used for large abscesses rather than a single long incision, which can create step-off deformities and delay wound healing. 2
- Post-procedure wound care involves simply covering the surgical site with a dry dressing—packing is not necessary and may cause more pain without improving healing. 1
- Needle aspiration has low success rates and is not recommended. 1
When Antibiotics Are NOT Needed
- Systemic antibiotics are usually unnecessary for uncomplicated furuncles after adequate incision and drainage. 1
- Most superficial abscesses can be adequately treated by drainage alone without antibiotics. 3
When to Add Systemic Antibiotics
Antibiotics should be added only in the following situations: 1
- Systemic inflammatory response syndrome or fever
- Extensive surrounding cellulitis
- Markedly impaired host defenses (immunocompromised patients)
- Multiple lesions
- Failure to respond to drainage alone
Antibiotic Selection When Indicated
- For methicillin-susceptible S. aureus (MSSA): oral penicillinase-resistant penicillins or first-generation cephalosporins 1
- For suspected MRSA: doxycycline, clindamycin, or trimethoprim-sulfamethoxazole 1
- In areas with high MRSA prevalence or in high-risk patients (previous MRSA infection, recent hospitalization, recent antibiotic use, long-term care facility residence, age >75 years), empiric MRSA coverage should be considered. 4
- Broad-spectrum antibiotics effective against aerobic and anaerobic organisms may be required in complicated cases, particularly in injecting drug users. 2
Management of Recurrent Boils
For patients experiencing recurrent furuncles: 1
- Evaluate for underlying causes such as hidradenitis suppurativa or retained foreign material
- Implement decolonization measures:
- Intranasal mupirocin application
- Daily chlorhexidine body washes
- Daily decontamination of personal items (towels, washcloths, clothing, bedding)
- Culture should be obtained in recurrent cases or treatment failures to guide antibiotic selection. 1
Critical Pitfalls to Avoid
- Never lance boils at home with needles or other non-sterile instruments—this can lead to severe invasive infections including osteomyelitis and bacteremia. 5
- Do not confuse simple furuncles with hidradenitis suppurativa, which requires different management strategies. 1
- Avoid antibiotic overuse for simple furuncles that have been adequately drained, as this contributes to antimicrobial resistance without improving outcomes. 1
- Do not use trimethoprim-sulfamethoxazole alone if there is concern for streptococcal infection, as Group A Streptococcus has intrinsic resistance. 4
- Recognize that carbuncles (coalescent furuncles) require more aggressive management than simple furuncles. 1
Special Populations
Injecting Drug Users
- Require special considerations with evaluation for endocarditis if persistent systemic signs are present 2
- Rule out foreign bodies (broken needles) by radiography 2
- Perform duplex sonography to identify vascular complications 2
- Screen for viral infections (HIV, HCV, HBV) 2
- Broad-spectrum antibiotics covering aerobic and anaerobic organisms are typically required 2