Urticaria

Definition

Urticaria (hives) is a skin reaction characterized by raised, itchy, red or skin-colored welts (wheals) caused by histamine release from mast cells. It may be acute (less than 6 weeks) or chronic (greater than 6 weeks).

Common Triggers

• Allergic reactions (foods, medications, insect stings)
• Infections
• Physical stimuli (cold, heat, pressure, sun)
• Stress
• Autoimmune disorders

Clinical Concerns

Urticaria may be a presenting sign of anaphylaxis. Monitor for angioedema, wheezing, hypotension. Life-threatening allergic reactions require immediate epinephrine IM.

Nursing Interventions

Identify and remove trigger, such as antihistamines (diphenhydramine, cetirizine), corticosteroids for severe cases (cool compresses). Avoid hot water and rough fabrics, for anaphylaxis, such as iM epinephrine first, then adjuncts.

NCLEX Relevance

Anaphylaxis with urticaria: IM epinephrine is first action.