Hives, also called urticaria, are raised, itchy welts that can appear anywhere on the skin and change shape or location within hours. They may be triggered by infection, medications, foods, heat, cold, pressure or other factors, but often no specific cause is found.
Symptoms
Welts may be skin-colored, pink or red and can merge into larger patches. Deeper swelling of the lips, eyelids, hands or feet is called angioedema. Individual hives usually fade within 24 hours, although new ones may appear.
Treatment
A non-drowsy antihistamine is usually first-line treatment. A pharmacist or clinician can advise on a suitable product and dose. Cool compresses, loose clothing and avoiding a clearly identified trigger may help. Do not stop an essential prescribed medication without medical advice.
When symptoms persist
Hives lasting or recurring for more than six weeks are called chronic urticaria and deserve assessment. Extensive allergy testing is not routinely useful unless the history suggests a specific trigger. Specialist treatments are available when standard antihistamines do not control symptoms.
Emergency signs
Call emergency services for swelling of the tongue or throat, breathing or swallowing difficulty, wheezing, faintness, confusion or collapse. These can indicate anaphylaxis. Use an epinephrine auto-injector immediately if one has been prescribed and follow the emergency plan.
Sources
- American Academy of Dermatology: Hives
- American Academy of Dermatology: Urticaria guideline
- MedlinePlus: Anaphylaxis
Reviewed: 28 August 2026