Light therapy of late luteal phase dysphoric disorder: an extended study

Nineteen patients with late luteal phase dysphoric disorder (LLPDD) and 11 healthy comparison subjects underwent a 3-month crossover trial of bright (more than 2500 lux) white morning, bright white evening, and placebo dim (less than 10 lux) red evening light, administered daily for 1 week during the premenstrual phase of the menstrual cycle. All light treatments significantly reduced depressive ratings from baseline levels.