The authors conclude that light therapy with continued SSRI treatment may be a useful strategy to achieve beneficial long-term effects in patients with SAD. A study by Lingjacrdc et al74 testing the hypothesis that Ginkgo biloba extract may prevent the symptoms of winter depression in patients with SAD yielded negative results. In a recent study metergoline, a nonspecific serotonin antagonist, did not demonstrate a sustained significant effect on mood compared with placebo.75 Table V.

Placebo-controlled studies of pharmacotherapy of seasonal affective disorder (SAD),58,67-75 Inhibitors,research,lifescience,medical General management issues Since there is little evidence comparing light therapy with antidepressant medication, the choice between these alternatives relies on individual assessment of risks and find protocol benefits.23 Generally, light therapy is very well accepted by patients. Availability and costs Inhibitors,research,lifescience,medical of a light therapy device are sometimes limiting factors, as is the time patients need to commit for daily light therapy. However, BLT should be considered first-line

treatment for moderately depressed patients and patients with prominent atypical depressive symptoms. Generally, light therapy alone Inhibitors,research,lifescience,medical or in combination with antidepressants should be given for the duration of the dark time of year, ie, until April or May in the northern hemisphere. A trial of light therapy should last at least 2 to 4 weeks. A trial of antidepressants should last 4 to 6 weeks. Light therapy and medication trials should be applied sequentially, as combining them from the beginning on will lead to a loss of information Inhibitors,research,lifescience,medical about which treatment is beneficial, or which treatment is causing side effects. A combination of both treatments should be considered if there is insufficient response to either pharmacological

or light treatment. If a depressive episode is resis] tant to the combination of BLT and an antidepressant, options are lengthening light treatment time, raising the t dose Inhibitors,research,lifescience,medical of the antidepressant, or switching to a drug of a dif5 ferent class. Although there are no specific data available for SAD, treatment should follow algorithms for treatment-resistant depression if a sufficient response still canl not be achieved. also Pharmacological augmentation strategies, electroconvulsive therapy, or sleep deprivation procedures80 should then be considered.
The Rarth ‘s rotation on its axis, the orbit of the Rarth around the Sun, and the orbit of the Moon around the Rarth induce rhythmic geophysical phenomena. Organisms are thus affected by daily and seasonal variations of many physical factors of their environment. The ability to adapt to this changing environment is an essential survival mechanism. As a result, life has evolved to adapt to periodically changing environmental demands, and to anticipate them according to their predictability.