The influence of light therapy in depressive patients

Our study investigated the effects of light therapy on mainly endogenously depressive patients. We applied white fluorescent light of 1500-2000 lux for a length of 4-6 hours daily. For 10 days no antidepressants or sleeping pills were given. We observed a quick and substantial improvement of depressive symptoms within 3 to 5 days. 9 patients showed a very good and 5 patients a good remission of symptoms. This corresponds to an improvement of 65% and is comparable to the effects of antidepressants. The improvement however with light is more rapid and more intensive, the main improvement is to be seen until the 5th day of treatment. No influence was found on vital signs or laboratory values. The rare side-effect was an increase in general drive and activity, which was perceived as agreeable however, and did not take the character of restlessness. Two times an increase of sexual drive was reported. The patients' self-rating concerning vital energy and concentration improved along with the values of the HDRS and CGI as with the quality of sleep. In general patients found light therapy to be agreeable. 1 patient only minimally improved (295.7). No improvement was to be seen in 5 patients (4 x 296.1, 309.1). From our findings we can conclude that light therapy in our patients had the same therapeutic efficacy as tricyclics. In our study the antidepressive effect of light could be maintained with Amitriptylin. Unlike other authors we did not observe a relapse into depression in the responders after ending light therapy.