Rash

A rash is a change in the skin's colour, texture or appearance. It may be itchy, painful, blistered, scaly or associated with illness. Infection, irritation, allergy and inflammatory conditions are possible causes. A rash is a description rather than a diagnosis, and accompanying symptoms determine how urgently it needs assessment.

What makes a rash useful to photograph?

Take clear images in good light, including both a close view and a wider view showing the location. Avoid filters. Photographs can help track change, but they do not show temperature, tenderness or how unwell a person feels.

Tell the clinician when it began, where it spread and whether it itches or hurts. Mention fever, new medicines, skin products, travel, sick contacts and possible exposures. Colour changes can appear differently across skin tones, so describe swelling, warmth and texture as well as redness.

For the Australian guidance behind this explanation, see Healthdirect Australia: Rashes - Healthdirect Australia.

Can I treat it before knowing the cause?

Gentle skin care and avoiding an obvious irritant may be reasonable for a mild, stable rash. However, applying several products or reusing a prescription for another condition can obscure the pattern or make it worse. Ask a pharmacist or doctor about suitable next steps.

A clinician may need an examination, swab or other test. If the rash persists or repeatedly returns, ask whether the diagnosis needs review. A remote image is helpful evidence, not a guarantee that every important cause can be excluded online.

When is it an emergency?

Call 000 for a rash with breathing difficulty, throat swelling, collapse or suspected severe allergic reaction. A rapidly worsening rash with fever, confusion, neck stiffness, severe pain or widespread blistering needs urgent assessment. Spots that do not fade when pressed are concerning in an unwell person, but absence of this sign does not rule out serious illness. Do not wait for routine online advice.

Where to go next

Read online doctor consultations to understand the relevant service. A doctor decides whether a consultation, examination, referral or another pathway is appropriate for your situation.