Some symptoms may require urgent medical evaluation. Know when to seek emergency care.
Hives are itchy, raised red patches on the skin that appear suddenly and can disappear within hours. They're usually an allergic reaction but can have other causes.
This content is for informational purposes only and does not substitute professional medical advice, diagnosis, or treatment. Always consult a qualified healthcare provider for medical concerns. In case of emergency, call 911 or your local emergency services immediately.
Hives appear as: • Red, itchy welts on skin • Raised, swollen patches • Can burn or sting • Variable sizes from small to large • Can appear anywhere on body
Last less than 6 weeks, often allergic.
Last more than 6 weeks, cause often unknown.
Triggered by heat, cold, pressure, or sunlight.
Swelling deeper in skin, often around eyes and lips.
Food, medication, or environmental allergens.
Cold, flu, or other viruses.
Can trigger or worsen hives.
Heat, cold, or water exposure.
Immune system attacking skin.
Common triggers include foods (nuts, shellfish, eggs), medications (antibiotics, NSAIDs), insect stings, latex, pollen, animal dander, physical factors (heat, cold, pressure), stress, and infections.
Seek immediate emergency care if hives are accompanied by difficulty breathing, swelling of the face, lips, tongue, or throat, wheezing, dizziness, fainting, or if you have a known severe allergy.
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January 2025
We regularly review and update our content to reflect the latest medical research and clinical practices.
The information provided on this website is for general informational purposes only and is not a substitute for professional medical advice, diagnosis, or treatment. Always consult a qualified healthcare provider for medical concerns. In case of emergency, call emergency services immediately.
Internal Medicine Physician
Internal Medicine
Dr. Rodriguez is a board-certified internist with expertise in primary care and preventive medicine.
Remember: In case of a medical emergency, call 911 immediately.
This page is for informational purposes only and does not replace professional medical advice.
