Erythema

Erythema — redness of the skin caused by increased blood flow through small vessels near the surface, often in response to irritation, inflammation, heat, or sun exposure. It is a visible sign rather than a diagnosis and can range from mild, temporary flushing to more persistent redness.

Key points

• Erythema occurs when superficial blood vessels dilate and fill with more blood, giving skin a pink or red appearance.
• It typically blanches, or briefly whitens, when pressed and returns once pressure is released.
• Common triggers include sunburn, irritation from products, heat, exercise, and inflammatory skin conditions.
• Persistent or spreading erythema, especially with pain, swelling, or fever, warrants evaluation by a healthcare professional.

Frequently asked

Is erythema the same as a rash?

Not exactly; erythema simply means redness from increased blood flow, while a rash may include additional features such as bumps, scaling, or texture changes.

Can skincare products cause erythema?

Yes; irritating or overly active ingredients can trigger temporary redness, which often eases when the product is paused and the barrier is supported.

Related topics

• What Is a Humectant?
• What Is the Skin Barrier?
• Post-Inflammatory Erythema (PIE)

This is a foundational entry in the SYNC Skin Encyclopedia and is expanded over time. Educational information only — not medical advice.