Skin Redness: Causes and When to Worry

What causes skin redness

Redness is a sign, not a diagnosis. Doctors narrow down the cause by its pattern: where it is, whether it itches or hurts, how fast it appeared, whether it is warm, and whether there are other symptoms.

Flushing

Flushing is sudden, temporary redness of the face, neck and upper chest. Triggers include heat, exercise, embarrassment, alcohol, spicy food and hot drinks. Recurrent flushing can come from rosacea, menopause hot flashes, some medicines (niacin, calcium channel blockers, vancomycin) and, rarely, carcinoid syndrome or other hormone-secreting tumors.

Inflammatory skin conditions

• Contact dermatitis: red, itchy, sometimes blistering skin where an irritant or allergen touched it, such as nickel, fragrance, hair dye, latex or poison ivy. Often has sharp edges or a shape matching the contact.
• Atopic dermatitis (eczema): dry, itchy, red patches in skin creases, often starting in childhood, with asthma or hay fever in the family.
• Seborrheic dermatitis: red, greasy, flaky patches on the scalp, eyebrows and sides of the nose.
• Psoriasis: well-defined red plaques with silvery scale on elbows, knees, scalp and lower back.
• Rosacea: persistent redness of the cheeks, nose and chin with flushing, small bumps and visible blood vessels, mostly in adults over 30.

Allergic reactions

• Hives: raised, itchy red welts that move around and fade within 24 hours.
• Drug rashes: widespread red spots a few days to 2 weeks after starting a medicine.
• Anaphylaxis: sudden widespread redness or hives with swelling and breathing problems.

Infections

• Cellulitis: a bacterial infection of the deeper skin, usually on one leg. Red, hot, swollen, tender and spreading, often with fever.
• Erysipelas: a more superficial infection with a raised, sharply defined, bright red edge, often on the face or legs.
• Fungal infections: red, ring-shaped or moist patches in skin folds, groin and feet.
• Viral rashes: measles, fifth disease ("slapped cheek") and scarlet fever cause widespread redness with fever.
• Shingles: a painful band of redness and blisters on one side of the body.

Physical and environmental causes

• Sunburn and heat rash
• Burns from heat, chemicals or friction
• Pressure: redness over bony areas in people who cannot move, an early sign of pressure sores
• Cold exposure and chilblains
• Photosensitivity reactions to sunlight after certain medicines

Circulation problems

• Stasis dermatitis: red-brown, itchy, scaly skin on swollen lower legs from poor vein function, often mistaken for cellulitis but affecting both legs.
• Blood clots (DVT): a red, warm, swollen calf.

Systemic diseases

Lupus (a butterfly-shaped facial rash), dermatomyositis (purplish eyelids and red knuckles) and liver disease (red palms) cause characteristic redness patterns.

Telling the causes apart

How a doctor diagnoses skin redness

Most causes are recognized by examining the skin and asking about triggers, timing, medicines and other symptoms. Tests may include skin scrapings for fungus, swabs for bacteria, patch testing for contact allergy, blood tests for infection or autoimmune disease, and occasionally a skin biopsy.

Treatment and home care

• Cool compresses for 10 to 15 minutes to calm hot, inflamed skin.
• Fragrance-free moisturizers applied several times a day for eczema and dry, irritated skin.
• Avoid triggers: identified allergens, harsh soaps, very hot showers, alcohol and spicy food for flushing.
• Over-the-counter hydrocortisone 1% cream for small areas of itchy dermatitis, following the label, for up to a week. Avoid it on infected skin and limit use on the face.
• Antihistamines for hives and itching, following the label dose.
• Sun protection: broad-spectrum SPF 30 or higher, shade and protective clothing.
• Prescription treatment: antibiotics for cellulitis, stronger steroid creams for eczema or psoriasis, and specific gels or tablets for rosacea.

Frequently asked questions

Why is my skin suddenly red?

Sudden redness is commonly caused by flushing (from heat, alcohol, emotion or exercise), an allergic reaction such as hives, contact with an irritant, or sunburn. If sudden redness comes with swelling of the face or throat, breathing difficulty or dizziness, call 911 or your local emergency number.

How can I tell if skin redness is an infection?

Infection is likely if the red area is warm, swollen, tender and spreading, especially over hours, or if you have fever, pus or red streaks. Draw around the edge with a pen; if it spreads beyond the line, see a doctor the same day.

What is the medical term for skin redness?

The medical term is erythema. It describes redness caused by widened, blood-filled small vessels in the skin. Many conditions include the word, such as erythema multiforme, erythema nodosum and palmar erythema, each describing a different pattern of redness.

What helps red, irritated skin?

Cool compresses, a gentle fragrance-free moisturizer and avoiding the trigger help most irritated skin. Short-term hydrocortisone cream can calm itchy dermatitis. See a doctor if redness is spreading, painful, blistering, comes with fever or does not improve in a week.