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How can I tell if my rash is an allergy?

Answered by the AskDoc Medical Team · Medically reviewed under our Medical Director, MBBS

Allergic hives are raised, intensely itchy wheals that move around, individual patches fading within hours as new ones appear. Contact allergy from products or metals stays put where the trigger touched, often with sharp borders.

Think back 24 to 48 hours: new detergent, cosmetic, plant contact, medicine or food. Stopping the suspect and antihistamines settle most episodes.

A rash with facial or tongue swelling, breathing difficulty or dizziness is an emergency. A rash with fever, blistering, or one that looks like bruising also needs same-day review rather than home detective work.

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For dry or itchy skin

Doctors reach for plain, fragrance-free creams like CeraVe or Cetaphil, not fancy actives. A thicker cream beats lotion, applied within minutes of washing while skin is still damp.

See fragrance-free creams

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