Skin Rashes: Common Causes & When to See a Doctor
A new rash can be alarming, but most are harmless and settle. Here's an overview of common causes and the signs that mean a rash needs to be seen.
Most rashes are harmless and short-lived
A non-fading rash with fever needs urgent care
Spreading or infected-looking? Get it assessed
Dermatology available within iCollab by referral
Rashes are very common and have a huge range of causes — most are harmless and short-lived. Knowing the general categories and the warning signs helps you decide when to simply wait and when to get checked.
Common causes
Rashes can come from irritation or allergic reactions (contact with something), eczema or other skin conditions, viral infections, heat, or reactions to medications, among many others. The appearance, location, timing, and any other symptoms all help point to the cause.
Related readingEczema & dermatitis explainedOne of the most common causes of an itchy, recurring rash.What can help
Avoiding known irritants, gentle skincare, and not scratching help many mild rashes. Because causes vary so widely, a rash that's spreading, persistent, or bothersome is best assessed rather than guessed at.
When to see a doctor — and when it's urgent
See a physician for a rash that's spreading quickly, painful, blistering, infected-looking, or not improving. Seek urgent care for a rash with difficulty breathing, facial or throat swelling, a fever with a rash that doesn't fade when pressed, or if you feel very unwell — these can signal a serious reaction or infection.
How iCollab can help
Our walk-in physicians can assess a rash, often the same day, and our dermatology team is available within iCollab by referral if specialist input helps.
This is general information, not medical advice. A non-fading rash with fever, or any breathing difficulty, needs urgent care.
Have a concern you'd like looked at?
Book with an iCollab physician, or ask at the walk-in clinic.
Skin Rashes: Common Causes & When to See a Doctor — FAQ
Most rashes — are they serious?+
When is a rash an emergency?+
What helps a mild rash?+
Can iCollab help?+
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