Erysipelas

Clinical Snapshot

Erysipelas is an acute, superficial infection of the upper dermis and lymphatics, most often caused by S. pyogenes, occurring most commonly on the face and lower extremities. It differs from ordinary cellulitis by its raised, sharply demarcated border and prominent lymphatic involvement. Recurrence occurs in up to 30% of cases.^[1] Narrow anti-streptococcal therapy is the default; broad MRSA treatment is not routine.

Recognize the Condition

Sharply demarcated, raised, erythematous plaque of facial erysipelas

Facial erysipelas — a raised, sharply demarcated erythematous plaque, distinguishing it from the diffuse border of ordinary cellulitis. (CDC/Dr. Thomas F. Sellers, Emory University — Public Health Image Library, public domain)

Abrupt onset of painful, warm, edematous plaque.
Raised, sharply defined edge rather than the diffuse border of cellulitis.
Peau d'orange (orange-peel) texture may occur, from dimpling around hair follicles.
Face and lower extremities are common sites.
Bullae can complicate more severe disease and may require extended treatment duration.^[2]

Risk Factors

Broken skin and wounds.
Chronic edema/lymphedema.
Tinea pedis and interdigital fissures.
Previous erysipelas/cellulitis.
Venous disease, obesity, diabetes, or immunosuppression.

Red Flags & Refer

Refer urgently for any of the following:

Bullous/necrotic change.
Systemic toxicity.
Hypotension.
Rapid progression.
Severe pain.
Facial infection with orbital concern.
An immunocompromised host with significant infection.
Possible necrotizing fasciitis.

Assessment & Diagnosis

Diagnosis is clinical. Document the sharply defined raised edge, site, systemic symptoms, and portal of entry. Routine culture is usually not possible unless there is an open lesion. Blood cultures are reserved for severe/systemic cases. Evaluate recurrent lower-limb disease for edema and tinea pedis, both correctable risk factors.

Treatment Targets

Rapidly control streptococcal infection.
Resolve pain, edema, and systemic symptoms.
Prevent deeper spread and recurrence.
Correct portals of entry and chronic edema.

Choose Initial Treatment

Direct treatment rule

Classic mild erysipelas

1st line: penicillin V or amoxicillin, narrow anti-streptococcal therapy.

Severe disease (systemic toxicity, rapid progression, severe pain, oral therapy unsuitable)

1st line (IV): penicillin G or cefazolin, and urgent higher-level assessment.

Beta-lactam allergy

Alternative: clindamycin.

Do not add MRSA-active therapy routinely unless there is a separate reason.

Non-Pharmacologic Treatment

Elevate the affected limb.
Use cool compresses for comfort.
Treat tinea pedis and skin fissures.
Manage chronic edema with compression once the acute phase permits — daily compression stocking use reduces recurrence.^[3]
Mark margins for objective follow-up.

Pharmacologic Treatment Options

Drug / intervention	Role	Dose / use	Important adverse effects	Teaching points
Penicillin V Preferred	Mild first-line therapy	300-600 mg PO QID for 5-10 days based on response	GI upset, hypersensitivity	Classic uncomplicated erysipelas where streptococci are strongly suspected.
Amoxicillin Preferred	Mild first-line therapy	500 mg PO TID or 875 mg PO BID	GI upset, hypersensitivity	Alternative narrow streptococcal therapy with more convenient dosing.
Cephalexin Alternative	When S. aureus coverage is also desired	500 mg PO QID	GI upset, hypersensitivity	Use when penicillin is not selected.
Clindamycin Alternative	Severe immediate beta-lactam allergy	300-450 mg PO TID	C. difficile infection risk	Use when local susceptibility supports it.
Penicillin G Preferred (parenteral)	Severe erysipelas	2-4 million units IV Q4-6H	Hypersensitivity, electrolyte load at high doses	For systemic toxicity, rapid progression, or inability to take oral treatment.
Cefazolin Alternative (parenteral)	Severe disease, hospital treatment	1-2 g IV Q8H	Hypersensitivity, phlebitis	When beta-lactam use is appropriate but penicillin G is not selected.
Vancomycin Special situation	Severe allergy, nonresponse, or MRSA concern	Institutional weight/AUC-guided IV dosing	Nephrotoxicity, infusion reaction	Reserve for selected severe cases with specialist monitoring.

Special Populations

Pregnancy

Penicillins and cephalosporins are preferred when the organism is susceptible. Clindamycin can be used for an appropriate severe beta-lactam allergy.

Recurrent lower-limb disease

Prioritize edema control, skin care, and treatment of interdigital fungal disease. Antibiotic prophylaxis is not first-line and should only be considered after recurrent episodes despite correction of modifiable risk factors.

Monitoring & Follow-Up

Review within 48-72 hours. Border expansion should stop, pain and fever should improve, and edema should begin to recede. Bullous change or systemic deterioration requires escalation. Duration can be extended when clinical response is incomplete.

Treatment Failure / Next Step

Confirm diagnosis and exclude cellulitis mimic.
Confirm beta-hemolytic streptococcal coverage and adherence.
Look for an occult abscess or deeper infection if purulence develops.
Reassess for necrotizing infection if pain/progression is severe.
Escalate to IV therapy or specialist care when response is inadequate.

Common Errors to Avoid

Using broad anti-MRSA therapy for classic uncomplicated erysipelas.
Failing to distinguish a raised sharp border from diffuse cellulitis.
Ignoring chronic edema and tinea pedis as correctable risk factors.
Treating severe facial or bullous disease entirely as an outpatient.

Clinical Decision Algorithm

Algorithm — Erysipelas

Sharply demarcated, raised, tender erythema/discoloration with peau d'orange, usually face or lower limb

Exclude necrotizing infection; facial disease in a child requires assessment for orbital/deep infection

Mild, systemically well

Penicillin V or amoxicillin PO; cephalexin is an alternative

Systemic toxicity, rapid progression, severe pain, bullae, major comorbidity, or oral therapy unsuitable

Urgent physician/hospital assessment; IV penicillin G or cefazolin; vancomycin for selected severe allergy/nonresponse

Drug Tables

How to use this table: Doses are adult doses and require patient-specific confirmation (renal/hepatic function, weight, allergy history). Pediatric dosing is weight-based per the current product monograph unless stated. Drug pricing is intentionally omitted. Select any drug name to open its complete Pharmasist Drug Database page.

Oral therapy (mild)

Drug	Dosage	Adverse effects	Comments
Penicillin V	Adults: 300-600 mg PO QID for 5-10 days based on response Children: 25-50 mg/kg/day divided Q6H PO (max 2000 mg/day)	GI upset, hypersensitivity	1st-line narrow streptococcal therapy.
Amoxicillin	Adults: 500 mg PO TID or 875 mg PO BID Children: Weight-based dosing per current product monograph	GI upset, hypersensitivity	Alternative narrow streptococcal therapy.
Cephalexin	Adults: 500 mg PO QID Children: 25-50 mg/kg/day divided Q6H PO	GI upset, hypersensitivity	When S. aureus coverage is also desired.
Clindamycin	Adults: 300-450 mg PO TID Children over 1 month: 25-40 mg/kg/day divided Q8H PO (max 450 mg/dose)	C. difficile infection risk	Severe beta-lactam allergy.

Parenteral therapy (severe)

Drug	Dosage	Adverse effects	Comments
Penicillin G	Adults: 2-4 million units IV Q4-6H Children and adolescents: 60,000-100,000 units/kg/dose Q6H IV (max 4 million units/dose)	Hypersensitivity, electrolyte load at high doses	1st-line for severe/systemic disease.
Cefazolin	Adults: 1-2 g IV Q8H Children: 50-100 mg/kg/day divided Q8H IV (max 6000 mg/day)	Hypersensitivity, phlebitis	Hospital alternative to penicillin G.
Vancomycin	Adults: 1 g Q12H (or 15 mg/kg Q8-12H) IV, institutional AUC monitoring Children: 45-60 mg/kg/day divided Q6-8H IV	Nephrotoxicity, infusion reaction	Selected severe allergy/nonresponse/MRSA concern.

References

Recurrent erysipelas--risk factors and clinical presentation — BMC Infectious Diseases (Inghammar M, Rasmussen M, Linder A). BMC Infect Dis 2014;14:270
Bullous erysipelas: a retrospective study of 26 patients — Journal of the American Academy of Dermatology (Guberman D, Gilead LT, Zlotogorski A, et al.). J Am Acad Dermatol 1999;41(5 Pt 1):733-737
Compression therapy to prevent recurrent cellulitis of the leg — New England Journal of Medicine (Webb E, Neeman T, Bowden FJ, et al.). N Engl J Med 2020;383(7):630-639
Practice guidelines for the diagnosis and management of skin and soft tissue infections: 2014 update by the Infectious Diseases Society of America — Clinical Infectious Diseases (Stevens DL, Bisno AL, Chambers HF, et al.). Clin Infect Dis 2014;59(2):e10-e52

Professional reference only. Apply clinical judgment and verify patient-specific decisions against current authoritative guidance and product information.