SOLAR URTICARIA
An allergic reaction to sunlight including UVA and UVB
Solar Urticaria (SU) is a rare disease that results in a physical response to UV or Visible light between 280nm and 780nm. Many people with SU will react through windows, and even on cloudy days. Fluorescent lights and computer monitors can be a problem after an extended exposure. Some report that they react to reflected light (UVB) from water, snow, sand, concrete, grass, glass buildings, shiny cars. Some even react to visible light. As seen in our photo gallery, people can react through their clothing, most dramatically seen with black and white stripes or polka dots.
It is important to understand what wavelengths of light cause your SU reactions in order to be able to protect yourself. Light testing can be performed by qualified medical professionals.