What Really Causes the Butterfly Rash in Lupus—and What to Do About It

Lupus, an autoimmune disease estimated to affect 1.5 million Americans, is often difficult to diagnose due to the wide array of symptoms it can cause. People with lupus may experience joint and muscle pain, fatigue, fever, hair loss, and anemia, to name just a handful.

While no single symptom is enough to confirm that someone has lupus (especially considering a lupus patient’s symptoms can change over time), there is one sign that occurs in 30% of patients: a facial rash that blooms across the cheeks and nose, commonly referred to as a lupus butterfly rash.

Also known as the malar rash, the butterfly rash is actually one of several skin concerns associated with lupus. Aside from its signature shape, it’s usually identified by its color and texture. Depending on the individual, the butterfly rash can range from a very light to deep shade of red, and sometimes it can be raised or scaly.

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This type of lupus face rash can occur when immune-related cells in a lupus patient’s skin react to damage from UV light exposure (from, for example, spending too much time in the sun) by releasing inflammatory chemicals, Amit Saxena, MD, a rheumatologist at NYU Langone’s Lupus Center, tells Health. “When the immune system turns on to ‘clean up’ damage from UV light,” he explains, “autoimmune inflammation can occur in that area.”

Why it often takes the shape of a butterfly remains unclear, Dr. Saxena adds, though he suggests that it could be because the cheeks and nose are usually subjected to more direct sunlight exposure than the upper lip.

When a butterfly rash flares up, Dr. Saxena says topical steroids can help decrease the inflammation, while oral steroids may provide people with “quick relief” in particularly severe cases. In general, though, he says that antimalarial and immunosuppressive medications will offer longer-term treatment. Where the former helps protect against damage from UV light exposure, the latter reduces inflammation and the body’s immune response.

It can be extremely difficult to prevent a flare-up of lupus symptoms. Dr. Saxena says triggers for a flare may include physical and emotional stress, as well as infections. But for lupus patients who experience the butterfly rash, using broad spectrum sunscreen, avoiding sunlight during peak hours, and covering up whenever they’re outside in the sun are important preventive measures.

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