ABSTRACT
Phototherapy of atopic dermatitis (AD) has been largely empirical since the beneficial effect of solar exposure has been appreciated for decades. In the early 1920s it was recognized that sea climate can improve AD and later it was appreciated that AD improved during the summer season. In 1948 the beneficial effects of phototherapy were studied in a systematic way by exposing patients to radiation emitted from carbon arc lamps. From the 1970s on, fluorescent lamps with more or less precisely defined emission spectra were applied, and these types of lamps are still in use. Within recent years new modalities like UVA1 and narrow band UVB were introduced. Although the basis of phototherapy of AD is still empirical today, parts of the new developments are already based on the advances in photoimmunology and molecular biology.
