What is the treatment for an infected piercing using cephalexin (antibiotic)?

Treatment of Infected Piercings with Cephalexin

Cephalexin is NOT the optimal first-line antibiotic for infected piercings because it lacks adequate coverage against Pseudomonas aeruginosa, the most common pathogen in cartilage piercings, and has suboptimal activity against community-acquired MRSA, which frequently causes soft tissue infections. 1

Pathogen-Specific Considerations

Cartilage Piercings (Ear, Nose)

• Pseudomonas aeruginosa is the predominant pathogen in auricular perichondritis and perichondrial abscesses, particularly within the first month after piercing 1
• Fluoroquinolones (ciprofloxacin or levofloxacin) are the recommended first-line agents for these infections, as they provide excellent coverage against P. aeruginosa, S. aureus, and S. pyogenes 1
• Cephalexin has no clinically relevant activity against Pseudomonas and should be avoided for cartilage piercing infections 2

Soft Tissue Piercings (Earlobe, Navel, Other)

• Staphylococcus aureus (including MRSA) and beta-hemolytic streptococci are the primary pathogens in non-cartilaginous piercing infections 1
• For simple soft tissue infections in areas with low MRSA prevalence, cephalexin 500 mg four times daily (or 250-500 mg QID) for 7-10 days may be considered 1, 3, 2
• In communities with high MRSA prevalence or when MRSA is suspected, alternatives such as clindamycin (300-450 mg TID-QID), doxycycline (100 mg BID), or trimethoprim-sulfamethoxazole are superior choices 1, 4

When Cephalexin May Be Appropriate

Cephalexin can be used for uncomplicated soft tissue piercing infections ONLY when:

• The infection involves non-cartilaginous tissue (earlobe, navel, soft tissue sites) 1
• Local MRSA prevalence is <10-15% 1, 4
• The patient has no penicillin allergy history involving anaphylaxis, angioedema, or urticaria (due to 10% cross-reactivity risk) 1, 3
• There is no purulent drainage suggesting MRSA 1

Dosing When Appropriate

• Adults: 500 mg orally four times daily OR 500 mg twice daily for 7-10 days 3, 2
• Children: 20 mg/kg per dose twice daily (maximum 500 mg per dose) for 7-10 days 3
• Duration: 7-10 days with clinical reassessment at 48-72 hours 1, 4

Critical Pitfalls to Avoid

Absolute Contraindications for Cephalexin

• Never use cephalexin for cartilage piercing infections (ear cartilage, nasal septum) due to lack of Pseudomonas coverage 1
• Avoid in patients with immediate penicillin hypersensitivity (anaphylaxis, angioedema, urticaria) due to up to 10% cross-reactivity 1, 3
• Do not use as empiric monotherapy in high-MRSA prevalence areas until susceptibility is confirmed 1, 4

Warning Signs Requiring Alternative Therapy

• Purulent drainage suggests MRSA and requires anti-MRSA coverage 1
• Systemic symptoms (fever, chills, spreading erythema) warrant broader coverage 1
• Failure to improve within 48-72 hours necessitates culture and antibiotic change 1, 4
• Auricular cartilage involvement (pain, warmth, sparing of earlobe) requires immediate fluoroquinolone therapy to prevent cartilage necrosis 1

Recommended Algorithm for Infected Piercings

Step 1: Identify piercing location

• Cartilage (ear, nose) → Use fluoroquinolone (ciprofloxacin or levofloxacin), NOT cephalexin 1
• Soft tissue (earlobe, navel, other) → Proceed to Step 2

Step 2: Assess for MRSA risk factors

• High local MRSA prevalence, purulent drainage, injection drug use, or previous MRSA → Use clindamycin, doxycycline, or TMP-SMX 1, 4
• Low MRSA risk → Cephalexin may be considered 1

Step 3: Verify allergy history

• History of anaphylaxis, angioedema, or urticaria to penicillins → Avoid cephalexin; use clindamycin or doxycycline 1, 3
• No severe allergy → Cephalexin acceptable if Steps 1-2 criteria met

Step 4: Adjunctive measures

• Remove jewelry if possible to facilitate drainage and healing 1
• Incision and drainage for abscesses is essential and may be curative even without antibiotics 1
• Reassess at 48-72 hours; obtain cultures if no improvement 1, 4

Bottom Line

For most infected piercings, cephalexin is NOT the optimal choice. Fluoroquinolones are superior for cartilage infections, and anti-MRSA agents (clindamycin, doxycycline, TMP-SMX) are preferred for soft tissue infections in the current era of community-acquired MRSA 1. Cephalexin should be reserved for uncomplicated soft tissue piercing infections in low-MRSA areas without penicillin allergy, and only after cartilage involvement has been excluded 1, 3, 2.