Understanding Erythema Multiforme

What is Erythema Multiforme?

Erythema multiforme (EM) is an acute, immune-mediated skin condition characterized by distinctive target-like rashes. It typically affects young adults and can range from mild to severe.

Types

• Minor form (EM minor): Affects only the skin
• Major form (EM major): More severe, involving mucous membranes

Common Causes

• Infections:
  • Herpes simplex virus (most common trigger)
  • Mycoplasma pneumoniae
• Medications:
  • Antibiotics
  • Anti-inflammatory drugs
  • Anticonvulsants

Symptoms

Skin Signs

• Target-shaped lesions ("bull's eye" appearance)
• Symmetric distribution on arms, legs, and face
• Red patches that may blister

Other Symptoms

• Mild fever
• Fatigue
• Joint aches
• Mouth sores (in EM major)

Diagnosis

• Clinical examination
• Detailed medical history
• Sometimes skin biopsy
• Review of recent medications

Treatment Options

General Measures

• Discontinuation of triggering medications
• Antiviral medicines if HSV-related
• Topical corticosteroids

Supportive Care

• Pain management
• Wound care for blisters
• Oral hygiene if mouth affected

Prevention

• Identify and avoid triggers
• Antiviral prophylaxis if HSV-related
• Regular medical follow-up

When to Seek Medical Care

• Extensive rash development
• Painful mouth sores
• Difficulty breathing or swallowing
• High fever

Prognosis

Most cases resolve within 2-4 weeks without scarring. Recurrence is possible, especially if triggered by HSV.