Treatments for classic (winter-based)<unk>  include light therapy, medication, ionized-air administration, cognitive-behavioral therapy and carefully timed supplementation of the hormone melatonin. Light therapy Photoperiod-related alterations of the duration of melatonin secretion may affect the<unk>  mood cycles of<unk> . This suggests that light therapy may be an<unk>  treatment for<unk> . Light therapy uses a lightbox which emits far more lumens than a customary incandescent lamp. Bright white "full spectrum" light at 10,000 lux, blue light at a wavelength of 480 nm at 2,500 lux or green (actually cyan or blue-green) light at a wavelength of 500 nm at 350 lux are used, with the first-mentioned historically preferred. Bright light therapy is<unk>  with the patient sitting a prescribed distance, commonly 30–60 cm, in front of the box with her/his eyes open but not staring at the light source for 30–60 minutes. A study published in May 2010 suggests that the blue light often used for<unk>  treatment should perhaps be replaced by green or white illumination. Discovering the best schedule is essential. One study has shown that up to 69% of patients find lightbox treatment inconvenient and as many as 19% stop use because of this. Dawn simulation has also proven to be<unk> ; in some studies, there is an 83% better response when compared to other bright light therapy. When compared in a study to negative air ionization, bright light was shown to be 57%<unk>  vs. dawn simulation 50%. Patients using light therapy can experience improvement during the first week, but increased results are evident when continued throughout several weeks. Certain symptoms like hypersomnia, early insomnia, social withdrawal, and anxiety resolve more rapidly with light therapy than with cognitive behavioral therapy. Most studies have found it<unk>  without use year round but rather as a<unk>  treatment lasting for several weeks until frequent light exposure is naturally obtained. Light therapy can also consist of exposure to sunlight, either by spending more time outside or using a computer-controlled heliostat to reflect sunlight into the windows of a home or office. Although light therapy is the leading treatment for<unk> , prolonged direct sunlight or artificial lights that don't block the ultraviolet range should be avoided due to the threat of skin cancer. The evidence base for light therapy as a preventive treatment for<unk>  is limited. The decision to use light therapy to treat people with a history of winter depression before depressive symptoms begin should be based on a persons preference of treatment. Medication SSRI (selective serotonin reuptake inhibitor) antidepressants have proven<unk>  in treating<unk> .<unk>  antidepressants are fluoxetine, sertraline, or paroxetine. Both fluoxetine and light therapy are 67%<unk>  in treating<unk>  according to direct head-to-head trials conducted during the 2006 Can-SAD study. Subjects using the light therapy protocol showed earlier clinical improvement, generally within one week of beginning the clinical treatment. Bupropion extended-release has been shown to prevent<unk>  for one in four people, but has not been compared directly to other preventive options in trials. In a 2021 updated Cochrane review of second-generation antidepressant medications for the treatment of<unk>  a definitive conclusion could not be drawn due to lack of evidence and the need for larger randomized controlled trials. Modafinil may be an<unk>  and well-tolerated treatment in patients with<unk> /winter depression. Another explanation is that vitamin D levels are too low when people do not get enough Ultraviolet-B on their skin. An alternative to using bright lights is to take vitamin D supplements. However, studies did not show a link between vitamin D levels and depressive symptoms in elderly Chinese nor among elderly British women given only 800IU when 6,000IU is needed. 5-HTP (an amino acid that helps to produce serotonin and is often used to help those with depression) has also been suggested as a supplement that may help treat the symptoms of<unk> , by lifting mood and regulating sleep schedule for sufferers. However, those who take antidepressants are not advised to take 5-HTP, as antidepressant medications may combine with the supplement to create dangerously high levels of serotonin – potentially resulting in 'serotonin syndrome'. Other treatments Depending upon the patient, one treatment (e.g., lightbox) may be used in conjunction with another (e.g., medication). Negative air ionization, which involves releasing charged particles into the sleep environment, has been found<unk>  with a 47.9% improvement if the negative ions are in sufficient density (quantity). Physical exercise has shown to be an<unk>  form of depression therapy, particularly when in addition to another form of treatment for<unk> . One particular study noted marked<unk> ness for treatment of depressive symptoms when combining regular exercise with bright light therapy. Patients exposed to exercise which had been added to their treatments in 20 minutes intervals on the aerobic bike during the day along with the same amount of time underneath the UV light were seen to make quick recovery. Of all the psychological therapies aimed at the prevention of<unk> , cognitive-behaviour therapy, typically involving thought records, activity schedules and a positive data log, has been the subject of the most empirical work, however, evidence for CBT or any of the psychological therapies aimed at preventing<unk>  remains inconclusive.
Seasonal affective disorder
Major depressive episode
Major depressive disorder
Depression 
Late life depression
Premenstrual syndrome
Secondary mania
Postpartum depression