Urticaria

Skin Lesion: Pruritic, erythematous, raised wheals (hives) with central pallor. Individual lesions are transient, typically appearing and disappearing within 24 hours without scarring.

Classification by Duration:

• Acute Urticaria: Symptoms lasting less than 6 weeks. Often triggered by infections, food, or medications.
• Chronic Urticaria: Symptoms occurring at least twice a week for more than 6 weeks. Often idiopathic or autoimmune.

Erythema Multiforme (EM)

• The Clue: Classic "Target" (Iris) lesions with three distinct zones: a dusky center, a pale ring, and an erythematous outer ring.
• Vs Urticaria: EM lesions are fixed (stay in the same spot for days); Urticaria wheals are migratory (shift within 24 hours).

Urticarial Vasculitis

• The Clue: Wheals that last longer than 24 hours and leave behind purpura or hyperpigmentation after resolving.
• Vs Urticaria: Patients often complain of burning/pain rather than itching.

🚨 Screen for Anaphylaxis immediately if:

• Angioedema: Swelling of the lips, tongue, or eyelids.
• Respiratory: Shortness of breath, wheezing, or stridor.
• Circulatory: Tachycardia, hypotension, or syncope.
• GI: Severe abdominal pain or vomiting following a trigger.

First-Line Treatment (2nd Gen Antihistamines):

• Loratadine: 10mg OD.
• Fexofenadine: 120mg or 180mg OD.
• Cetirizine 10mg OD.
  [Child: 0.25mg/kg OD]
• Desloratadine 5mg OD
  [Child: 0.1mg/kg OD] (non-drowsy)

Step-Up Therapy (Chronic/Refractory):

• Increase 2nd Gen Antihistamine dose up to 4x the standard dose.
• Piriton: 4mg ON (Add-on for nocturnal itch).

Acute Flare Support:

• Prednisolone: 30mg–50mg OD for 3–5 days.
  [Child: 1-2mg/kg OD] (max: 60mg).

⚠️ Emergency Dosing: For Anaphylaxis, IM Adrenaline (1:1000) 0.5mg immediately in the mid-outer thigh.

📸 Images